Multilayer ceramic capacitor

ABSTRACT

A multilayer ceramic capacitor includes a multilayer body, and external electrodes on a portion of a side surface portion including four side surface of the multilayer body, and on a portion of a first main surface of the multilayer body. The first main surface includes first regions covered with the external electrodes and a second region exposed from the external electrodes. The first regions of the first main surface each include recesses therein. The recesses in each of the first regions each include a spherical curved wall surface. The recesses in each of the first regions each have an average inlet size of about 0.3 μm or more and about 10.5 μm or less.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on and claims the benefit of priority fromJapanese Patent Application No. 2021-042346, filed on Mar. 16, 2021, thecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a multilayer ceramic capacitor.

2. Description of the Related Art

Conventionally, multilayer ceramic capacitors are used in electronicequipment such as mobile phones and portable music players. Suchmultilayer ceramic capacitors each generally include a ceramic base bodyas a multilayer body including internal electrode layers, each having anend portion exposed on the surface, and external electrodes, eachprovided to cover the portion where the internal electrode layers of theceramic base body are exposed. Examples of the external electrodesinclude a sintered metal film formed by applying and firing a conductivepaste as described in Japanese Unexamined Patent Application PublicationNo. 2002-203737, and a plating film formed as described in JapaneseUnexamined Patent Application Publication No. 2004-327983.

However, in multilayer ceramic capacitors such as those described inJapanese Unexamined Patent Application Publication No. 2002-203737 andJapanese Unexamined Patent Application Publication No. 2004-327983, whenthe adhesion force between the ceramic base body and the externalelectrode is weak, moisture or the like is likely to penetrate from theinterface between the ceramic base body and the external electrode,leading to a problem in that the moisture resistance of the multilayerceramic capacitor may be reduced.

SUMMARY OF THE INVENTION

Preferred embodiments of the present invention provide multilayerceramic capacitors that are each able to reduce or prevent a decrease inmoisture resistance.

A multilayer ceramic capacitor according to a preferred embodiment ofthe present disclosure includes a multilayer body including a pluralityof laminated dielectric layers and a plurality of laminated internalelectrode layers, the multilayer body further including a first mainsurface and a second main surface which oppose each other in alamination direction, a first side surface and a second side surfacewhich oppose each other in a length direction perpendicular orsubstantially perpendicular to the lamination direction, and a thirdside surface and a fourth side surface which oppose each other in awidth direction perpendicular or substantially perpendicular to thelamination direction and the length direction, and a plurality ofexternal electrodes on a portion of a side surface portion including thefour side surfaces, and on a portion of the first main surface, thefirst main surface further including a plurality of first regionscovered with the plurality of external electrodes and a second regionexposed from the plurality of external electrodes, the plurality offirst regions of the first main surface each including a plurality ofrecesses therein, the plurality of recesses in each of the plurality offirst regions each including a spherical curved wall surface, and theplurality of recesses in each of the plurality of first regions eachhaving an average inlet size of about 0.3 μm or more and about 10.5 μmor less.

According to preferred embodiments of the present invention, it ispossible to provide multilayer ceramic capacitors that are each able toreduce or prevent a decrease in moisture resistance.

The above and other elements, features, steps, characteristics andadvantages of the present invention will become more apparent from thefollowing detailed description of the preferred embodiments withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of a multilayer ceramic capacitoraccording to a preferred embodiment of the present invention.

FIG. 2 is an arrow view when viewing a second side surface of themultilayer ceramic capacitor shown in FIG. 1 along the direction of thearrow II.

FIG. 3 is an arrow view when viewing a first main surface of themultilayer ceramic capacitor shown in FIG. 2 along the direction of thearrow III.

FIG. 4 is a cross-sectional view taken along the line IV-IV of themultilayer ceramic capacitor shown in FIG. 1 .

FIG. 5 is a cross-sectional view taken along the line V V of themultilayer ceramic capacitor shown in FIG. 4 .

FIG. 6 is a cross-sectional view taken along the line VI-VI of themultilayer ceramic capacitor shown in FIG. 4 .

FIG. 7 is a diagram corresponding to FIG. 3 , which is an arrow viewwhen viewing a first main surface of the multilayer ceramic capacitorshown in FIG. 2 along the direction of the arrow III, and is a virtualview showing a multilayer body when excluding external electrodes.

FIG. 8A is an enlarged view schematically showing a microscopic state ina plan view of the surface of a first region of the multilayer body.

FIG. 8B is an enlarged cross-sectional view schematically showing across-section in the vicinity of a surface layer portion of themultilayer body along the line VIIIB-VIIIB of the surface in FIG. 8A.

FIG. 9A is a diagram of another preferred embodiment of the presentinvention of a plurality of recesses provided on the surface of thefirst region of the multilayer body, and corresponding to FIG. 8A.

FIG. 9B is a diagram of another preferred embodiment of the presentinvention of a plurality of recesses provided on the surface of thefirst region of the multilayer body, and corresponding to FIG. 8B.

FIG. 10A is a diagram of another preferred embodiment of the presentinvention of a plurality of recesses provided on the surface of thefirst region of the multilayer body, and corresponding to FIG. 8A.

FIG. 10B is a diagram of another preferred embodiment of the presentinvention of a plurality of recesses provided on the surface of thefirst region of the multilayer body, and corresponding to FIG. 8B.

FIG. 11A is a cross-sectional view of a first modified example of amultilayer ceramic capacitor according to a preferred embodiment of thepresent invention, and corresponding to FIG. 4 . FIG. 11B is across-sectional view showing a second modified example of a multilayerceramic capacitor according to a preferred embodiment of the presentinvention, and corresponding to FIG. 4 .

FIG. 12 is a cross-sectional view showing a third modified example of amultilayer ceramic capacitor according to a preferred embodiment of thepresent invention, and corresponding to FIG. 4 .

FIG. 13A is a diagram of a fourth modified example of the multilayerceramic capacitor according to a preferred embodiment of the presentinvention, and corresponding to FIG. 2 .

FIG. 13B is an arrow view when viewing a second main surface of themultilayer ceramic capacitor shown in FIG. 13A along the direction ofthe arrow XIIIB.

FIG. 14A is a diagram of a fifth modified example of the multilayerceramic capacitor according to a preferred embodiment of the presentinvention, and corresponding to FIG. 2 .

FIG. 14B is an arrow view when viewing the first main surface of themultilayer ceramic capacitor shown in FIG. 14A along the direction ofthe arrow XIVB.

FIG. 14C is an arrow view when viewing the third side surface of themultilayer ceramic capacitor shown in FIG. 14B along the direction ofthe arrow XIVC.

FIG. 15 is a diagram of a sixth modified example of the multilayerceramic capacitor according to a preferred embodiment of the presentinvention, and corresponding to FIG. 2 .

FIG. 16A is a diagram of a second preferred embodiment of the presentinvention, and shows a state in which a multilayer ceramic capacitor isembedded in a component built-in board.

FIG. 16B is an enlarged view of an XVIB portion in FIG. 16A, and is anenlarged cross-sectional view schematically showing a microscopiccross-sectional shape in the vicinity of a surface layer portion of asecond region of a multilayer body.

FIG. 17 is an external perspective view of a multilayer ceramiccapacitor according to a third preferred embodiment of the presentinvention.

FIG. 18 is an exploded perspective view of the multilayer body includedin the multilayer ceramic capacitor according to the third preferredembodiment of the present invention.

FIG. 19 is an external perspective view of the multilayer body includedin the multilayer ceramic capacitor according to the third preferredembodiment of the present invention.

FIG. 20A is an arrow view when viewing the first main surface of themultilayer ceramic capacitor shown in FIG. 17 along the direction of thearrow XXA.

FIG. 20B is an arrow view when viewing the first main surface of themultilayer body shown in FIG. 19 along the direction of the arrow XXB.

FIG. 21 is an external perspective view of a multilayer ceramiccapacitor of a first modified example of a preferred embodiment of thepresent invention, and corresponding to FIG. 17 .

FIG. 22 is an external perspective view of a multilayer ceramiccapacitor of a second modified example of a preferred embodiment of thepresent invention, and corresponding to FIG. 17 .

FIG. 23 is an exploded perspective view of a multilayer body included inthe multilayer ceramic capacitor of the second modified example of apreferred embodiment of the present invention, and corresponding to FIG.18 .

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be described belowwith reference to the drawings.

First Preferred Embodiment

Hereinafter, a multilayer ceramic capacitor 1 according to a firstpreferred embodiment of the present disclosure will be described. FIG. 1is an external perspective view of the multilayer ceramic capacitor 1according to the first preferred embodiment. FIG. 2 is an arrow viewwhen viewing a fourth side surface WS2 of the multilayer ceramiccapacitor 1 shown in FIG. 1 along the direction of the arrow II. FIG. 3is an arrow view when viewing a first main surface TS1 of the multilayerceramic capacitor 1 shown in FIG. 2 along the direction of the arrowIII. FIG. 4 is a cross-sectional view taken along the line IV-IV of themultilayer ceramic capacitor 1 shown in FIG. 1 . FIG. 5 is across-sectional view taken along the line V-V of the multilayer ceramiccapacitor 1 shown in FIG. 4 . FIG. 6 is a cross-sectional view takenalong the line VI-VI of the multilayer ceramic capacitor 1 shown in FIG.4 .

The multilayer ceramic capacitor 1 includes a multilayer body 10 andexternal electrodes 40.

The XYZ Cartesian coordinate system is shown in FIGS. 1 to 6 . Themultilayer ceramic capacitor 1 and the multilayer body 10 each have alength direction L corresponding to the X direction. The multilayerceramic capacitor 1 and the multilayer body 10 each have a widthdirection W corresponding to the Y direction. The multilayer ceramiccapacitor 1 and the multilayer body 10 each have a lamination (stacking)direction T corresponding to the Z direction. Herein, the cross sectionshown in FIG. 4 is also referred to as an LT cross section. The crosssection shown in FIG. 5 is also referred to as a WT cross section. Thecross section shown in FIG. 6 is also referred to as an LW crosssection.

As shown in FIGS. 1 to 6 , the multilayer body 10 includes a first mainsurface TS1 and a second main surface TS2 which oppose each other in thelamination direction T, a first side surface LS1 and a second sidesurface LS2 which oppose each other in the length direction Lperpendicular or substantially perpendicular to the lamination directionT, and a third side surface WS1 and a fourth side surface WS2 whichoppose each other in the width direction W perpendicular orsubstantially perpendicular to the lamination direction T and the lengthdirection L.

The multilayer body 10 has a rectangular or substantially rectangularparallelepiped shape. The dimension of the multilayer body 10 in thelength direction L is not necessarily longer than the dimension of thewidth direction W. The multilayer body 10 preferably includes roundedcorners and ridges. The corners are portions where the three surfaces ofthe multilayer body intersect, and the ridges are portions where the twosurfaces of the multilayer body intersect.

The dimensions of the multilayer body 10 are not particularly limited,but when the dimension in the length direction L of the multilayer body10 is defined as the L dimension, the L dimension is preferably about0.01 mm or more and about 10 mm or less, for example. Furthermore, whenthe dimension in the width direction W of the multilayer body 10 isdefined as a W dimension, the W dimension is preferably about 0.01 mm ormore and about 10 mm or less, for example. When the dimension in thelamination direction T of the multilayer body 10 is a T dimension, the Tdimension is preferably about 0.01 mm or more and about 0.2 mm or less,for example.

The multilayer body 10 includes an inner layer portion 11, and a firstmain surface-side outer layer portion 12 and a second main surface-sideouter layer portion 13 which sandwich the inner layer portion 11 in thelamination direction T.

The inner layer portion 11 includes a plurality of dielectric layers 20and a plurality of internal electrode layers 30. The inner layer portion11 includes, in the lamination direction T, internal electrode layers 30from the internal electrode layer 30 located closest to the first mainsurface TS1 to the internal electrode layer 30 located closest to thesecond main surface TS2. In the inner layer portion 11, a plurality ofinternal electrode layers 30 oppose each other to each other with thedielectric layer 20 interposed therebetween. The inner layer portion 11generates a capacitance and substantially functions as a capacitor. Theinner layer portion 11 is also referred to as an effective layerportion.

The plurality of dielectric layers 20 are each made of a dielectricmaterial. The dielectric material may be, for example, a dielectricceramic including components such as a BaTiO₃, CaTiO₃, SrTiO₃, orCaZrO₃. Furthermore, the dielectric material may be obtained by adding asub-component such as, for example, a Mn compound, an Fe compound, a Crcompound, a Co compound, or a Ni compound to the main component.

The average particle size of the ceramic particles used in thedielectric layer 20 is preferably, for example, about 0.1 μm or more andabout 1 μm or less, and more preferably about 0.1 μm or more and about0.5 μm or less. Thus, it is possible to reduce the thickness of thedielectric layer 20 of the multilayer ceramic capacitor 1, and thus itis possible to obtain the multilayer ceramic capacitor 1 with a largecapacitance density per volume.

The thickness of the dielectric layer 20 is preferably about 0.2 μm ormore and about 10 μm or less, for example. The number of the dielectriclayers 20 to be laminated (stacked) is preferably 4 or more and 700 orless, for example. The number of the dielectric layers 20 refers to thetotal number of dielectric layers in the inner layer portion 11, anddielectric layers in the first main surface-side outer layer portion 12and the second main surface-side outer layer portion 13.

The plurality of internal electrode layers 30 each include a pluralityof first internal electrode layers 31 and a plurality of second internalelectrode layers 32. The plurality of first internal electrode layers 31are each provided on the dielectric layer 20. The plurality of secondinternal electrode layers 32 are each provided on the second dielectriclayer 20. The plurality of first internal electrode layers 31 and theplurality of second internal electrode layers 32 are alternatelyprovided via the dielectric layer 20 in the lamination direction T ofthe multilayer body 10. The first internal electrode layers 31 and thesecond internal electrode layers 32 each sandwich the dielectric layers20.

The first internal electrode layer 31 includes a first opposing portion31A facing the second internal electrode layer 32, and a first lead-outportion 31B extending from the first opposing portion 31A toward thefirst side surface LS1. The first lead-out portion 31B is exposed on thefirst side surface LS1.

The second internal electrode layer 32 includes a second opposingportion 32A facing the first internal electrode layer 31, and a secondlead-out portion 32B extending from the second opposing portion 32Atoward the second side surface LS2. The second lead-out portion 32B isexposed on the second side surface LS2.

In the present preferred embodiment, the first opposing portion 31A andthe second opposing portion 32A are opposed to each other with thedielectric layers 20 interposed therebetween, such that a capacitance isgenerated, and the characteristics of a capacitor are provided.

The shapes of the first opposing portion 31A and the second opposingportion 32A are not particularly limited. However, they are preferablyrectangular or substantially rectangular. However, the corners of therectangular or substantially rectangular shape may be rounded, or thecorners of the rectangular or substantially rectangular shape may beslanted. The shapes of the first lead-out portion 31B and the secondlead-out portion 32B are not particularly limited. However, they arepreferably rectangular or substantially rectangular. However, thecorners of the rectangular or substantially rectangular shape may berounded, or the corners of the rectangular or substantially rectangularshape may be slanted.

The dimension in the width direction W of the first opposing portion 31Amay be the same or substantially the same as the dimension in the widthdirection W of the first lead-out portion 31B, or either of them may besmaller. The dimension in the width direction W of the second opposingportion 32A may be the same or substantially the same as the dimensionin the width direction W of the second lead-out portion 32B, or eitherof them may be smaller.

The first internal electrode layer 31 and the second internal electrodelayer 32 are each made of an appropriate conductive material including ametal such as, for example, Ni, Cu, Ag, Pd, and Au, and an alloyincluding at least one of these metals. When using an alloy, the firstinternal electrode layer 31 and the second internal electrode layer 32may be made of, for example, a Ag—Pd alloy or the like.

The thickness of each of the first internal electrode layers 31 and thesecond internal electrode layers 32 is preferably, for example, about0.2 μm or more and about 2.0 μm or less. The total number of the firstinternal electrode layers 31 and the second internal electrode layers 32is preferably, for example, 4 or more and 200 or less.

The first main surface-side outer layer portion 12 is located in thevicinity of the first main surface TS1 of the multilayer body 10. Thefirst main surface-side outer layer portion 12 includes a plurality ofdielectric layers 20 located between the first main surface TS1 and theinternal electrode layer 30 closest to the first main surface TS1. Thedielectric layers 20 used in the first main surface-side outer layerportion 12 may be the same as the dielectric layers 20 used in the innerlayer portion 11.

The second main surface-side outer layer portion 13 is located in thevicinity of the second main surface TS2 of the multilayer body 10. Thesecond main surface-side outer layer portion 13 includes a plurality ofdielectric layers 20 located between the second main surface TS2 and theinternal electrode layer 30 closest to the second main surface TS2. Thedielectric layers 20 used in the second main surface-side outer layerportion 13 may be the same as the dielectric layers 20 used in the innerlayer portion 11.

The multilayer body 10 includes a counter electrode portion 11E. Thecounter electrode portion 11E refers to a portion where the firstopposing portion 31A of the first internal electrode layer 31 and thesecond opposing portion 32A of the second internal electrode layer 32oppose each other. The counter electrode portion 11E defines andfunctions as a portion of the inner layer portion 11. FIG. 6 shows therange of the counter electrode portion 11E in the width direction W andin the length direction L. The counter electrode portion 11E is alsoreferred to as a capacitor active portion.

The multilayer body 10 includes side surface-side outer layer portionsWG. The side surface-side outer layer portions include a first sidesurface-side outer layer portion LG1 and a second side surface-sideouter layer portion LG2. The first side surface-side outer layer portionLG1 includes the dielectric layer 20 and the first lead-out portion 31Blocated between the counter electrode portion 11E and the first sidesurface LS1. The second side surface-side outer layer portion LG2includes the dielectric layer 20 and the second lead-out portion 32Blocated between the counter electrode portion 11E and the second sidesurface LS2. FIGS. 4 and 6 each show the ranges in the length directionL of the first side surface-side outer layer portion LG1 and the secondside surface-side outer layer portion LG2. The first side surface-sideouter layer portion and the second side surface-side outer layer portionmay also be referred to as end surface-side outer layer portions, Lgaps, or end gaps.

Furthermore, the side surface-side outer layer portion includes a thirdside surface-side outer layer portion WG1 and a fourth side surface-sideouter layer portion WG2. The third side surface-side outer layer portionWG1 includes a dielectric layer 20 located between the counter electrodeportion 11E and the third side surface WS1. The fourth side surface-sideouter layer portion WG2 includes the dielectric layers 20 locatedbetween the counter electrode portion 11E and the fourth side surfaceWS2. FIGS. 5 and 6 each show the ranges of the third side surface-sideouter layer portion WG1 and the fourth side surface-side outer layerportion WG2 in the width direction W. The third side surface-side outerlayer portion and the fourth side surface-side outer layer portion mayalso be referred to as W gaps or side gaps.

The external electrode 40 includes a plurality of external electrodes,each provided on a portion of the side surface including the four sidesurfaces LS1, LS2, WS1, and WS2, and a portion of the first main surfaceTS1. In the present preferred embodiment, the external electrode 40includes a first external electrode 40A provided in the vicinity of thefirst side surface LS1, and a second external electrode 40B provided inthe vicinity of the second side surface LS2.

The first external electrode 40A is provided at least on a portion ofthe first side surface LS1 and a portion of the first main surface TS1.In the present preferred embodiment, more specifically, the firstexternal electrode 40A extends from the first side surface LS1 to aportion of the first main surface TS1. That is, as shown in the LTcross-section of FIG. 4 , the cross-sectional shape of the firstexternal electrode 40A of the present preferred embodiment is L-shaped.The first external electrode 40A is connected to the first internalelectrode layer 31.

The second external electrode 40B is provided at least on a portion ofthe second side surface LS2 and on a portion of the first main surfaceTS1. In the present preferred embodiment, more specifically, the secondexternal electrode 40B extends from the second side surface LS2 as aportion of the side surface portion to a portion of the first mainsurface TS1. That is, as shown in the LT cross-section of FIG. 4 , thecross-sectional shape of the second external electrode 40B of thepresent preferred embodiment is L-shaped. The second external electrode40B is connected to the second internal electrode layers 32.

As described above, in the multilayer body 10, the capacitance isgenerated by the first opposing portions 31A of the first internalelectrode layers 31 and the second opposing portions 32A of the secondinternal electrode layers 32 opposing each other with the dielectriclayers 20 interposed therebetween. Therefore, characteristics of thecapacitor are developed between the first external electrode 40A towhich the first internal electrode layers 31 are connected and thesecond external electrode 40B to which the second internal electrodelayers 32 are connected.

The first external electrode 40A includes a first base electrode layer50A and a first plated layer 60A provided on the first base electrodelayer 50A.

The second external electrode 40B includes a second base electrode layer50B and a second plated layer 60B provided on the second base electrodelayer 50B.

The first base electrode layer 50A and the second base electrode layer50B each include, for example, at least one selected from a fired layer,a thin film layer, and other layers.

In the present preferred embodiment, the first base electrode layer 50Aand the second base electrode layer 50B are thin film layers. The thinfilm layer is a layer on which metal particles are deposited.

When the first base electrode layer 50A and the second base electrodelayer 50B are each made of a thin film layer, they are preferablyproduced by a thin film forming method such as a sputtering method or anevaporation method, for example. Herein, a sputtering electrode formedby a sputtering method will be described.

The first base electrode layer 50A of the present preferred embodimentis defined by the first thin film layer 51A including the sputteringelectrode. The second base electrode layer 50B is defined by a secondthin film layer 51B including the sputtering electrode. When forming thebase electrode layer with a sputtering electrode, it is preferable toform a sputtering electrode directly on at least one portion of eitherthe first main surface TS1 or the second main surface TS2 of themultilayer body 10. In the present preferred embodiment, the first thinfilm layer 51A including the sputtering electrode is provided on aportion of the first main surface TS1 in the vicinity of the first sidesurface LS1. The second thin film layer 51B including the sputteringelectrode is provided on a portion on the first main surface TS1 in thevicinity of the second side surface LS2.

The thin film layer including the sputtering electrode preferablyincludes at least one metal selected from the group consisting of, forexample, Mg, Al, Ti, W, Cr, Cu, Ni, Ag, Co, Mo and V. Thus, it ispossible to increase the adhesion of the external electrode 40 to themultilayer body 10. The thin film layer may be a single layer or mayinclude a plurality of layers. For example, the thin film layer mayinclude a two-layer structure including a layer of Ni—Cr alloy and alayer of Ni—Cu alloy.

The thickness of the sputtering electrode in the lamination directionconnecting the first main surface TS1 and the second main surface TS2 ispreferably about 50 nm or more and about 400 nm or less, and morepreferably about 50 nm or more and about 130 nm or less.

When providing the base electrode layer by directly forming a sputteringelectrode on at least one of the first main surface TS1 and the secondmain surface TS2 of the multilayer body 10, it is preferable to providea base electrode layer defining and functioning as a fired layer on thefirst side surface LS1 and the second side surface LS2, or alternativelyit is preferable to directly provide a plated layer to be describedlater without providing the base electrode layer. In the presentpreferred embodiment, a plated layer to be described later is directlyprovided on the first side surface LS1 and the second side surface LS2without providing a base electrode layer.

As described later in the first and second modified example of apreferred embodiment of the present invention, the first base electrodelayer 50A and the second base electrode layer 50B may be fired layers,for example. It is preferable that the fired layer includes a metalcomponent, and either a glass component or a ceramic component, or ametal component and both of the glass component and the ceramiccomponent. The metal component includes, for example, at least oneselected from Cu, Ni, Ag, Pd, Ag—Pd alloys, Au, and the like. The glasscomponent includes, for example, at least one selected from B, Si, Ba,Mg, Al, Li, and the like. For the ceramic component, a ceramic materialof the same kind as that of the dielectric layer 20 may be used, or aceramic material of a different kind may be used. The ceramic componentincludes, for example, at least one selected from BaTiO₃, CaTiO₃, (Ba,Ca) TiO₃, SrTiO₃, CaZrO₃, and the like.

The fired layer is, for example, a fired conductive paste includingglass and metal applied to the multilayer body 10. The fired layer maybe a laminate chip including internal electrode layers and dielectriclayers and a conductive paste applied to the laminate chipsimultaneously fired, or may be a laminate chip having internalelectrode layers and dielectric layers fired to obtain the multilayerbody 10, following which a conductive paste may be applied to themultilayer body 10 and fired. In a case of simultaneously firing thelaminate chip including the internal electrode layers and dielectriclayers, and a conductive paste applied to the laminate chip, it ispreferable that the fired layer be formed by firing a material to whicha ceramic material, instead of glass component, is added. In this case,it is particularly preferable to use, as the ceramic material to beadded, the same type of ceramic material as the dielectric layer 20.Furthermore, the fired layer may include a plurality of layers.

Alternatively, the first plated layer 60A and the second plated layer60B described later may be directly provided on the multilayer body 10without providing the first base electrode layer 50A and the second baseelectrode layer 50B.

The first plated layer 60A covers the first base electrode layer 50A.

The second plated layer 60B covers the second base electrode layer 50B.

The first plated layer 60A and the second plated layer 60B may includeat least one selected from, for example, Cu, Ni, Sn, Ag, Pd, Ag—Pdalloys, Au, or the like. Each of the first plated layer 60A and thesecond plated layer 60B may include a plurality of layers.

When the multilayer ceramic capacitor 1 is mounted on the board surface,the first plated layer 60A and the second plated layer 60B arepreferably a two-layer structure including a Sn plated layer on a Niplated layer. In this case, the Ni plated layer prevents the first baseelectrode layer 50A and the second base electrode layer 50B from beingeroded by solder when mounting the multilayer ceramic capacitor 1.Furthermore, the Sn plated layer improves the wettability of the solderwhen mounting the multilayer ceramic capacitor 1. This facilitates themounting of the multilayer ceramic capacitor 1.

A Cu plated layer may be provided between the base electrode layer andthe Ni plated layer. Furthermore, when directly providing the platedlayer on the multilayer body 10 without providing the base electrodelayer, the Cu plated layer may be provided between the Ni plated layerand the multilayer body. In a case of providing the Cu plated layer, itis possible to achieve an advantageous effect of reducing or preventingthe penetration of a plating solution or moisture.

The plated layer of the present preferred embodiment includes athree-layer structure including a Cu plated layer defining andfunctioning as a lower plated layer, a Ni plated layer defining andfunctioning as an intermediate plated layer, and a Sn plated layerdefining and functioning as an upper plated layer. That is, the firstplated layer 60A includes a first Cu plated layer 61A, a first Ni platedlayer 62A, and a first Sn plated layer 63A. The second plated layer 60Bincludes a second Cu plated layer 61B, a second Ni plated layer 62B, anda second Sn plated layer 63B.

The first Cu plated layer 61A covers the first side surface LS1 of themultilayer body 10 and the first base electrode layer 50A provided onthe first main surface TS1 of the multilayer body 10. The first Niplated layer 62A covers the first Cu plated layer 61A. The first Snplated layer 63A covers the first Ni plated layer 62A.

The second Cu plated layer 61B covers the second side surface LS2 of themultilayer body 10 and the second base electrode layer 50B provided onthe first main surface TS1 of the multilayer body 10. The second Niplated layer 62B covers the second Cu plated layer 61B. The second Snplated layer 63B covers the second Ni plated layer 62B layer.

In the present preferred embodiment, the first plated layer 60A isdirectly electrically connected to the first internal electrode layer31. Furthermore, the second plated layer 60B is directly electricallyconnected to the second internal electrode layer 32.

By providing a plated layer including a Cu plated layer and Ni platedlayer so as to cover the base electrode layer, the base electrode layeris prevented from being eroded by solder at the time of mounting themultilayer ceramic capacitor 1. Furthermore, by providing the Sn platedlayer on the surface of the Ni plated layer, the wettability of thesolder when mounting the multilayer ceramic capacitor 1 is improved.Thus, it is possible to easily mount the multilayer ceramic capacitor 1.

The thickness per plated layer is preferably about 2 μm or more andabout 15 μm or less, for example. That is, the average thickness of eachof the first Cu plated layer 61A, the first Ni plated layer 62A, thefirst Sn plated layer 63A, the second Cu plated layer 61B, the second Niplated layer 62B, and the second Sn plated layer 63B is preferably about2 μm or more and about 15 μm or less, for example. More specifically,the average thickness of each of the first Cu plated layer 61A and thesecond Cu plated layer 61B is more preferably about 5 μm or more andabout 8 μm or less, for example. Furthermore, the average thickness ofeach of the first Ni plated layer 62A, the first Sn plated layer 63A,the second Ni plated layer 62B, and the second Sn plated layer 63B ismore preferably about 2 μm or more and about 4 μm or less, for example.

As described in the second preferred embodiment of the present inventionbelow, when embedding the multilayer ceramic capacitor 1 in the board,the plated layer preferably includes the outermost layer made of a Cuplated layer, for example.

The external electrode 40 may include only a plated layer withoutproviding the first base electrode layer 50A and the second baseelectrode layer 50B. That is, the multilayer ceramic capacitor 1 mayinclude a plated layer that is directly electrically connected to thefirst internal electrode layer 31 and the second internal electrodelayer 32. In such a case, the plated layer may be provided after thecatalyst is provided on the surface of the multilayer body 10 as apretreatment.

When providing the plated layer directly on the multilayer body 10, itis possible to reduce the thickness of the base electrode layer.Therefore, since the dimension of the multilayer ceramic capacitor 1 inthe lamination direction T is reduced by the amount of reducing thethickness of the base electrode layer, it is possible to reduce theheight of the multilayer ceramic capacitor 1. Alternatively, when thethickness of the dielectric layer 20 sandwiched between the firstinternal electrode layer 31 and the second internal electrode layer 32is increased by the amount of reducing the thickness of the baseelectrode layer, it is possible to improve the thickness of the basebody. Thus, by providing the plated layer directly on the multilayerbody 10, it is possible to improve the degrees of freedom in design ofthe multilayer ceramic capacitor.

Here, the basic configurations of each layer included in the firstexternal electrode 40A and the second external electrode 40B are thesame or substantially the same. Furthermore, the first externalelectrode 40A and the second external electrode 40B are plane symmetricor substantially plane symmetric with respect to the WT cross-section atthe middle in the length direction L of the multilayer ceramic capacitor1. Therefore, in a case in which it is not necessary to particularlydistinguish between the first external electrode 40A and the secondexternal electrode 40B, the first external electrode 40A and the secondexternal electrode 40B may be collectively referred to as an externalelectrode 40. The same applies to the respective layers included in thefirst external electrode 40A and the second external electrode 40B. Forexample, in a case in which it is not necessary to particularlydistinguish between the first base electrode layer 50A and the secondbase electrode layer 50B, the first base electrode layer 50A and thesecond base electrode layer 50B may be collectively referred to as abase electrode layer 50. Furthermore, in a case in which it is notnecessary to particularly distinguish between the first thin film layer51A and the second thin film layer 51B, the first thin film layer 51Aand the second thin film layer 51B may be collectively referred to as athin film layer 51. Furthermore, in a case in which it is not necessaryto particularly distinguish between the first plated layer 60A and thesecond plated layer 60B, the first plated layer 60A and the secondplated layer 60B may be collectively referred to as a plated layer 60.Furthermore, in a case in which it is not necessary to particularlydistinguish between the first Cu plated layer 61A and the second Cuplated layer 61B, the first Cu plated layer 61A and the second Cu platedlayer 61B may be referred to collectively as a Cu plated layer 61.Furthermore, in a case in which it is not necessary to particularlydistinguish between the first Ni plated layer 62A and the second Niplated layer 62B, the first Ni plated layer 62A and the second Ni platedlayer 62B may be collectively referred to as a Ni plated layer 62.Furthermore, in a case in which it is not necessary to particularlydistinguish between the first Sn plated layer 63A and the second Snplated layer 63B, the first Sn plated layer 63A and the second Sn platedlayer 63B may be collectively referred to as a Sn plated layer 63.

FIG. 7 is a diagram corresponding to FIG. 3 , which is an arrow viewwhen viewing the first main surface TS1 of the multilayer ceramiccapacitor 1 shown in FIG. 2 along the direction of the arrow III, and avirtual view showing the multilayer body 10 when excluding the externalelectrode 40.

As shown in FIG. 7 , the first main surface TS1 of the multilayer body10 includes a plurality of first regions A1 covered with the firstexternal electrode 40A and the second external electrode 40B definingand functioning as the plurality of external electrodes 40. Furthermore,the first main surface TS1 of the multilayer body 10 includes a secondregion A2 exposed from the first external electrode 40A and the secondexternal electrode 40B defining and functioning as the plurality ofexternal electrodes 40.

In the present preferred embodiment, the plurality of first regions A1are divided into a region TS1A covered by the first external electrode40A and a region TS1B covered by the second external electrode 40B. Thatis, the plurality of first regions A1 are separated from each other inthe length L direction, and include the two regions of the region TS1Alocated in the vicinity of the first side surface LS1 and the regionTS1B located in the vicinity of the second side surface LS2.Furthermore, the second region A2 is provided between the plurality offirst regions A1 so as to separate the plurality of first regions A1.

As shown in FIGS. 2 and 3 , the first external electrode 40A covers therange from the first side surface LS1 over the distance L1 in the lengthdirection toward the second side surface LS2 on the first main surfaceTS1 of the multilayer body 10. The second external electrode 40B coversthe range from the second side surface LS2 over the distance L1 in thelength direction toward the first side surface LS1 on the first mainsurface TS1 of the multilayer body 10. Furthermore, in the first mainsurface TS1 of the multilayer body 10, the region between the areacovered by the first external electrode 40A and the area covered by thesecond external electrode 40B is exposed, and the length of the exposedportion in the length direction is defined as the distance L2.

With reference to FIG. 7 , the range extending from the first sidesurface LS1 toward the second side surface LS2 to the distance L1 in thelength direction corresponds to the region TS1A, on the first mainsurface TS1 of the multilayer body 10. Furthermore, the range from thesecond side surface LS2 toward the first side surface LS1 to thedistance L1 in the length direction corresponds to the region TS1B, onthe first main surface TS1 of the multilayer body 10.

That is, the distance in the length direction of each of the pluralityof first regions A1 corresponds to the distance L1, and the distance inthe length direction of the second region A2 corresponds to the distanceL2.

FIG. 8A is an enlarged view of a VIIIA portion which is a portion of thesurface of the first region A1 of the multilayer body 10 in FIG. 7 , andis an enlarged view schematically showing a microscopic state when thesurface of the multilayer body 10 is viewed in plane. FIG. 8B is anenlarged cross-sectional view schematically showing a cross-section inthe vicinity of the surface layer portion of the multilayer body 10along the line VIIIB-VIIIB of the surface in FIG. 8A. However, FIG. 8Bschematically shows an enlarged cross-sectional view in a state wherethe external electrode 40 is provided on the surface of the multilayerbody 10. That is, for convenience of explanation, an enlarged view ofthe FIG. 8A is a diagram showing a state in which the external electrode40 is excluded, while an enlarged cross-sectional view of the FIG. 8B isa diagram of a state in which the external electrode 40 is provided.

Here, as described above, the basic configurations of the first externalelectrode 40A and the second external electrode 40B are the same orsubstantially the same. Therefore, in the following explanation of FIG.8B and the like, the first external electrode 40A and the secondexternal electrode 40B are described as an external electrode 40. Thesame applies to the respective layers included in the first externalelectrode 40A and the second external electrode 40B. As shown in FIG.8B, on the dielectric layer 20 included in the multilayer body 10, thethin film layer 51 defining and functioning as the base electrode layer50 is provided. Furthermore, the plated layer 60 covers the baseelectrode layer 50. The plated layer 60 includes, for example, a Cuplated layer 61, a Ni plated layer 62, and a Sn plated layer 63.

As shown in FIGS. 8A and 8B, the first region A1 of the first mainsurface TS1 of the multilayer body 10 includes a plurality of recesses80 provided therein, each having a spherical curved surface.

The plurality of recesses 80 are provided in a large number in the firstregion A1 of the surface of the dielectric layer 20 included in themultilayer body 10. In the present preferred embodiment, the pluralityof recesses 80 having the same or substantially the same size areprovided in a plane.

As shown in FIG. 8A, the plurality of recesses 80 may be provided in ahexagonal close-packed shape on the surface of the dielectric layer 20.By providing the plurality of recesses 80 in the hexagonal close-packedshape, it is possible to provide the plurality of recesses 80 on thesurface of the dielectric layer 20 at a high density. For example, theplurality of recesses 80 may be provided such that an average of 5 ormore and 7 or less other recesses 80 are positioned around one recess80. Thus, it is possible to provide the plurality of recesses 80 on thesurface of the dielectric layer 20 at a high density. The plurality ofrecesses 80 may be regularly provided. Alternatively, they may not beregularly provided.

Each of the plurality of recesses 80 includes an opening 81, and a wallsurface 82. As shown FIG. 8A, in the present preferred embodiment, theopening 81 defining the outer edge portion of the recess 80 is in acircular or substantially circular shape.

As its cross-sectional shape is shown in FIG. 8B, the wall surface 82 ofthe recess 80 includes a spherical curved surface, for example. That is,the wall surface 82 of the recess 80 includes a concave curved surfacewhich defines a portion of the surface of the sphere. The wall surfaceof the recess 80 may have a hemispherical shape, for example.Alternatively, the wall surface 82 of the recess 80 may have aspherically curved surface less than a hemisphere, for example.

The first region A1 of the first main surface TS1 of the multilayer body10 includes a plurality of recesses 80, each having a spherical curvedsurface, and a land portion 90 as a region in which the plurality ofrecesses 80 are not provided.

The average inlet size of the plurality of recesses 80 provided in thefirst region A1 is about 0.3 μm or more and about 10.5 μm or less, forexample. When the average inlet size of the recess 80 is smaller thanabout 0.3 μm, since the contact area between the external electrode 40and the multilayer body 10 is reduced, it is difficult to sufficientlyobtain an anchor effect between the external electrode 40 and themultilayer body 10. Therefore, it is difficult to increase the adhesionstrength between the external electrode 40 and the multilayer body 10,and there is a possibility that the moisture resistance reliability isreduced. On the other hand, when the average inlet size of the recess 80is larger than about 10.5 μm, the stress tends to concentrate on therecess 80, so that the strength of the multilayer body 10 may be loweredand cracks may occur. The average inlet size of the plurality ofrecesses 80 provided in the first region A1 is preferably about 0.3 μmor more and about 3.2 μm or less, for example. When the average inletsize of the recess 80 is about 0.3 μm or more and about 3.2 μm or less,the occurrence of cracks can be further reduced or prevented. Inaddition, the wall surface 82 of the recess 80 includes a sphericalcurved surface, such that the external electrode 40 is likely to enterthe plurality of recesses 80, a result of which the adhesion between theexternal electrode 40 and the multilayer body 10 is increased.

In addition, the average inlet size of the plurality of recesses 80provided in the first region A1 is preferably, for example, about twiceor more and about 20 times or the less the average particle size of theceramic particles included in the dielectric layer 20, and morepreferably twice or more and 10 times or less. For example, the averageparticle size of the ceramic particles may be about 0.1 μm or more andabout 1 μm or less, and the average inlet size of the plurality ofrecesses 80 provided in the first region A1 may be set to be about twiceor more and about 20 times or less the average particle size of theceramic particles. For example, the average particle size of the ceramicparticles may be set to about 0.1 μm or more and about 0.5 μm or less,and the average inlet size of the plurality of recesses 80 provided inthe first region A1 may be set to about twice or more and about 10 timesor less the average particle size of the ceramic particles. Thus, it ispossible to appropriately provide the recess 80, while ensuring theanchor effect between the external electrode 40 and the multilayer body10, and it is also possible to reduce or prevent the stressconcentration on the multilayer body 10. Therefore, it is possible toachieve both the adhesion strength between the external electrode 40 andthe multilayer body 10 and the strength of the multilayer body 10.

The average inlet size of the plurality of recesses 80 provided in thefirst region A1 may be, for example, about 0.2 times or more and about 5times or less the thickness of the dielectric layer 20 sandwichedbetween the first internal electrode layer 31 and the second internalelectrode layer 32. For example, as the ceramic particles included inthe dielectric layer 20, smaller ceramic particles having, for example,the average particle size of about 1 μm or less or about 0.5 μm or lessmay be used, the thickness of the dielectric layer 20 sandwiched betweenthe first internal electrode layer 31 and the second internal electrodelayer 32 may be, for example, set to about 0.2 μm or more and about 4 μmor less, or may be, for example, about 0.2 μm or more and about 2 μm orless, and furthermore, the average inlet size of the plurality ofrecesses 80 provided in the first region A1 may be, for example, set toabout 0.2 times or more and about 5 times or less the thickness of thedielectric layer 20 sandwiched between the first internal electrodelayer 31 and the second internal electrode layer 32. Thus, the use ofappropriate ceramic particles having a smaller average particle sizemakes it possible to appropriately provide the recess 80, whileincreasing the capacitance density by reducing the thickness of thedielectric layer 20 sandwiched between the first internal electrodelayer 31 and the second internal electrode layer 32. Therefore, it ispossible to ensure the capacitance density per volume of the multilayerceramic capacitor 1, and also ensure the adhesion strength between theexternal electrode 40 and the multilayer body 10.

In the first region A1, the area ratio R occupied by the opening 81 ofthe plurality of recesses 80 is preferably about 52% or more, forexample. Thus, the anchor effect between the external electrode 40 andthe multilayer body 10 is increased, and thus it is possible to increasethe adhesion strength between the external electrode 40 and themultilayer body 10. As a result, the advantageous effect of reducing orpreventing the intrusion of moisture or the like from the interfacebetween the multilayer body 10 and the external electrode 40 isincreased, and thus it is possible to further improve the moistureresistance reliability of the multilayer ceramic capacitor 1. When thearea ratio is smaller than about 52%, since the contact area between theexternal electrode 40 and the multilayer body 10 is reduced, the degreeof increase in anchor effect between the external electrode 40 and themultilayer body 10 is reduced.

The average depth of the plurality of recesses 80 provided in the firstregion A1 is preferably about 0.1 μm or more and about 5 μm or less, andmore preferably about 0.2 μm or more and about 3 μm or less, forexample. Thus, it is possible to reduce or prevent the stressconcentration on the multilayer body 10, while ensuring the anchoreffect between the external electrode 40 and the multilayer body 10, andthus it is possible to achieve both the adhesion strength between theexternal electrode 40 and the multilayer body 10, and the strength ofthe multilayer body 10.

Here, the depth of the recess 80 is defined as the maximum value of thedistance in the depth direction of the recess 80 from the deepestportion of the recess 80 to the opening 81 of the recess 80.

The average depth of the plurality of recesses 80 provided in the firstregion A1 may be, for example, about 25% or more and about 50% or lessthe average inlet size of the plurality of recesses 80.

In addition, the average depth of the plurality of recesses 80 providedin the first region A1 is preferably, for example, about 1.0 times ormore and about 10 times or less the average particle size of the ceramicparticles included in the dielectric layer 20, and more preferably abouttwice or more and about 10 times or less, for example. Thus, it ispossible to appropriately provide the recess 80, and reduce or preventthe stress concentration on the multilayer body 10, while ensuring theanchor effect between the external electrode 40 and the multilayer body10. Therefore, it is possible to achieve both the adhesion strengthbetween the external electrode 40 and the multilayer body 10, and thestrength of the multilayer body 10.

In addition, the average depth of the plurality of recesses 80 providedin the first region A1 may be larger than the thickness of the baseelectrode layer 50, and may be smaller than the thickness of the platedlayer 60 defining and functioning as an outer electrode layer coveringthe base electrode layer 50. That is, when the external electrode 40includes at least the base electrode layer 50 provided in close contactwith the plurality of first regions A1 of the first main surface TS1,and the outer electrode layer covering the base electrode layer 50, thethickness of the base electrode layer 50 may be smaller than the averagedepth of the plurality of recesses 80, and the thickness of the outerelectrode layer may be larger than the average depth of the plurality ofrecesses 80. Here, the base electrode layer 50 is defined by the thinfilm layer 51 such as a sputtering electrode, for example. The outerelectrode layer is defined by a plated layer 60 covering the thin filmlayer 51. Thus, it is possible to increase the anchor effect between theplurality of recesses 80 of the multilayer body 10 covered by the thinfilm layer 51 and the plated layer 60 included in the external electrode40, while increasing the adhesion by increasing the contact area betweenthe surface of the multilayer body 10 and the thin film layer 51, andthus it is possible to increase the adhesion strength between theexternal electrode 40 and the multilayer body 10 as a whole.

The configuration of the present preferred embodiment is more effectivefor the multilayer body 10 having a smaller dimension in the laminationdirection T. For example, it is more effective for the multilayerceramic capacitor 1 having the multilayer body 10 in which the dimensionin the lamination direction T is about 0.01 mm or more and about 0.2 mmor less. As the dimension in the lamination direction T of themultilayer body 10 is smaller, since the mechanical strength of themultilayer body 10 is likely to decrease, it is strongly required tosecure both the mechanical strength of the multilayer body 10, and theadhesion strength between the external electrode 40 and the multilayerbody 10.

The configuration of the plurality of recesses 80 provided in the firstregion A1 is not limited to that shown in FIGS. 8A and 8B. For example,the configuration of the plurality of recesses 80 may be as shown inFIGS. 9A and 9B. FIGS. 9A and 9B are diagrams showing an example ofanother configuration of the plurality of recesses 80 provided on thesurfaces of the first regions A1 of the multilayer body 10, and arediagrams corresponding to FIGS. 8A and 8B, respectively.

In the configurations shown in FIGS. 9A and 9B, a plurality of recesses80, each having a spherical curved surface, are provided in the firstregion A1 on the first main surface TS1 of the multilayer body 10. Here,the plurality of recesses 80 may have recesses of different inlet sizes.For example, as shown in FIGS. 9A and 9B, the plurality of recesses 80may include recesses 80B each having a larger inlet size with respect tothe average inlet size, and recesses 80C each having a smaller inletsize with respect to the average inlet size. In this case, the averagedepth of the recesses 80C, each having an inlet size smaller than theaverage inlet size, may be smaller than the average depth of therecesses 80B, each having a larger inlet size with respect to theaverage inlet size. Thus, it is possible to appropriately adjust theanchor effect between the external electrode 40 and the multilayer body10. In addition, the recesses 80B each having a larger inlet size withrespect to the average inlet size, and the recesses 80C each having asmaller inlet size with respect to the average inlet size may beregularly provided, or alternatively may not be regularly provided.Furthermore, the plurality of recesses 80 may have inlet sizes which aredifferent randomly or in a stepwise manner.

The plurality of recesses 80B and 80C having different inlet sizesinclude circular or substantially circular openings 81B and 81C, andwall surfaces 82B and 82C having spherical curved surfaces. In addition,the openings 81B and 81C are not limited to a circular substantiallycircular shape, and may be in another shape. In addition, for example,the wall surface 82B of the recess 80B may be a hemispherical-shaped orsubstantially hemispherical-shaped surface, or may be a spherical-shapedsurface less than hemispherical, and the wall surface 82C of the recess80C may be a spherical curved surface less than hemispherical.

In this case as well, the average inlet size of the plurality ofrecesses 80 provided in the first region A1 is preferably about 0.3 μmor more and about 10.5 μm or less, for example. Furthermore, in thefirst region A1, the area ratio occupied by the openings of theplurality of recesses 80 is preferably about 52% or more, for example.Furthermore, the average depth of the plurality of recesses 80 providedin the first region A1 is preferably about 0.1 μm or more and about 5 μmor less, and more preferably about 0.2 μm or more and about 3 μm orless, for example.

Moreover, the configuration of the plurality of recesses 80 provided inthe first region A1 is acceptable as shown in FIGS. 10A and 10B. FIGS.10A and 10B are diagrams showing an example of another configuration ofthe plurality of recesses 80 provided on the surfaces of the firstregions A1 of the multilayer body 10, and are diagrams corresponding toFIGS. 8A and 8B, respectively.

In the configurations shown in FIGS. 10A and 10B, a plurality ofrecesses 80 each having a spherical curved surface are provided in thefirst region A1 on the first main surface TS1 of the multilayer body 10.Here, the plurality of recesses 80 may each include a recess 80D inwhich an opening 81D has a hexagonal or substantially hexagonal shape.As a result, the plurality of recesses 80 can be provided at a higherdensity in the first region A1. Therefore, it is possible toappropriately ensure the anchor effect between the external electrode 40and the multilayer body 10.

Even in this case, the wall surface 82D of the recess 80D has aspherical curved surface. That is, the wall 82D of the recess 80D has aconcave curved surface so as to define a portion of the surface of thesphere.

In this case, it is preferable that the average inlet size of theplurality of recesses 80 provided in the first region A1 is about 0.3 μmor more and about 10.5 μm or less, for example. Furthermore, in thefirst region A1, the area ratio occupied by the openings of theplurality of recesses 80 is preferably about 52% or more, for example.Furthermore, the average depth of the plurality of recesses 80 providedin the first region A1 is preferably about 0.1 μm or more and about 5 μmor less, and more preferably about 0.2 μm or more and about 3 μm orless, for example.

In addition, the recesses as shown FIGS. 8A and 8B, the recesses havingdifferent inlet sizes as shown in FIGS. 9A and 9B, and the recesseshaving different shapes of openings as shown in FIGS. 10A and 10B maycoexist in the first region A1.

Hereinafter, a non-limiting example of a method of measuring variousparameters in the present preferred embodiment will be described.

A method for measuring the average inlet size of the recesses providedon the surface of the multilayer body will be described. The inlet sizeof the recess is calculated as the circle equivalent size of an openingof the recess. Here, the circle equivalent size indicates the diameterof a true circle corresponding to the area of a measurement targetportion.

First, the external electrodes are removed using a plating release agentor other agents so as not to cause damage to the multilayer body. Then,in the middle portion in the width direction and the length direction ofthe first region A1, the surface of the multilayer body is photographedwith a scanning electron microscope (SEM) or an atomic force microscope(AFM). The photographing condition is set such that individual ceramicparticles can be distinguished, a plurality of irregularities areincluded in the field of view, and the three-dimensional shape of theirregularities can be confirmed. For example, in the case of SEM, about5,000 times to about 20,000 times is a standard. Thereafter, the averageinlet size of the recesses is calculated using the captured image in thefollowing manner.

(1) Identify the outline of the outer edge of the recess and identifythe opening of the recess.

(2) Perform processing of (1) on a plurality of recesses within theobservation range. The observation range is set so that the number ofrecesses is 20 or more.

(3) Use the image processing software, and calculate the circleequivalent size of the opening of each recess as the inlet size of therecess.

(4) Set the average value of the inlet size of the plurality of recessescalculated in (3), as the average inlet size of the recess.

A non-limiting example of a method for measuring the area ratio Roccupied by the opening of the plurality of recesses in the first regionA1 of the surface of the multilayer body will be described. Here, thearea ratio R occupied by the opening of the recess is calculated by theratio of the total area of the first region A1 including the landportions and the plurality of recesses within the observation range,relative to the summed area of the openings of the plurality of recessesprovided in the observation range.

First, the external electrodes are removed using a plating release agentor other agents so as not to cause damage to the multilayer body. Then,in the middle portion in the width direction and the length direction ofthe first region A1, the surface of the multilayer body is photographedwith a scanning electron microscope (SEM) or an atomic force microscope(AFM). The photographing condition is set such that individual ceramicparticles can be distinguished, a plurality of irregularities areincluded in the field of view, and the three-dimensional shape of theirregularities can be confirmed. For example, in the case of SEM, about5,000 times to about 20,000 times is a standard. Thereafter, the arearatio R occupied by the openings of the plurality of recesses iscalculated using the captured image in the following manner.

(1) Identify the outline of the outer edge of the recess and identifythe opening of the recess.

(2) Perform processing of (1) on a plurality of recesses within theobservation range. The observation range is set so that the number ofrecesses is 20 or more.

(3) Use the image processing software, and for each recess, calculatethe area of the region surrounded by the outline of the outer edge ofthe recess as the area of the opening of the recess.

(4) Calculate the ratio occupied by the summed area of the openings ofthe plurality of recesses calculated in (3) with respect to the area ofthe entire observation range, as the area ratio R occupied by theopenings of the plurality of recesses.

A non-limiting example of a method for measuring the depth of the recessprovided on the surface of the multilayer body will be described. First,polishing is performed without damaging the multilayer body, and a crosssection perpendicular or substantially perpendicular to the widthdirection of the multilayer body is exposed. Next, the cross section ofthe first region A1 of the surface of the multilayer body isphotographed by a scanning electron microscope (SEM) or a scanning ionmicroscope (SIM). The photographing condition is set such that it ispossible to distinguish individual ceramic particles, and a plurality ofirregularities in the field of view are included. For example, in thecase of SEM, about 5,000 times to about 20,000 times is a standard.Thereafter, the depth of the plurality of recesses is measured by thefollowing method using the photographed cross-sectional image.

(1) Set the observation range so that the number of recesses is 20 ormore.

(2) For one of the recesses of (1), identify two vertices indicating theopening of the recess and the lowest point indicating the deepestportion of the recess in the cross-sectional image.

(3) Obtain the length connecting the midpoint of the straight lineconnecting the two vertices identified in (2) and the lowest point ofthe recess identified in (2) as the depth of one recess.

(4) Perform processing of (1) to (3) for a plurality of recesses withinthe observation range, and calculate the average value of the depth ofthe plurality of recesses calculated within the observation range, asthe depth of the recess.

A non-limiting example of a method for measuring the thickness of thedielectric layer sandwiched between a plurality of internal electrodelayers will be described. First, a cross section perpendicular orsubstantially perpendicular to the length direction of the multilayerbody exposed by polishing is observed by a scanning electron microscope(SEM). Next, the thickness of the dielectric layer 20 on a total of fivelines including the center line along the lamination direction passingthrough the center of the cross section of the multilayer body, and twolines drawn at equal or substantially equal intervals on both sides fromthe center line are measured. This measurement is performed for each ofthe upper portion, the intermediate portion, and the lower portion inthe lamination direction, and the average value of these measurements iscalculated as the thickness of the dielectric layer 20 of the presentpreferred embodiment.

A non-limiting example of a method of measuring each layer included inthe external electrode such as the base electrode layer, the platedlayer, and other layers will be described. First, a cross sectionperpendicular or substantially perpendicular to the length direction ofthe multilayer body exposed by polishing is observed by a scanningelectron microscope (SEM). Next, five lines are provided at equal orsubstantially equal intervals which are perpendicular or substantiallyperpendicular to the extending direction of the measurement targetlayer, and the thicknesses of the measurement target layer on the fivelines are measured. Then, the average value of the thickness of themeasurement target layer on the five lines is calculated as thethickness of the measurement target layer of the present preferredembodiment.

A non-limiting example of a method for measuring the average particlesize of the ceramic particles included in the dielectric layer will bedescribed. First, a cross section perpendicular or substantiallyperpendicular to the length direction of the multilayer body exposed bypolishing is observed by a scanning electron microscope (SEM). Then, theparticle sizes of 200 particles are measured using a diameter methodwhich defines the maximum length of each particle in the directionparallel to the internal electrode as the particle size, and the averagevalue is calculated as the average particle size.

Next, a non-limiting example of a method of manufacturing the multilayerceramic capacitor 1 according to the present preferred embodiment willbe described.

A dielectric sheet for the dielectric layer 20 and a conductive pastefor the internal electrode layer 30 are provided. The conductive pastefor the dielectric sheet and the internal electrode includes a binderand a solvent. A known binder and solvent may be used. A paste made of aconductive material is, for example, one in which an organic binder andan organic solvent are added to a metal powder.

On the dielectric sheet, a conductive paste for the internal electrodelayer 30 is printed in a predetermined pattern by, for example, screenprinting or gravure printing. Thus, the dielectric sheet in which thepattern of the first internal electrode layer 31 is provided, and thedielectric sheet in which the pattern of the second internal electrodelayer 32 is provided are prepared.

A predetermined number of dielectric sheets in which the pattern of theinternal electrode layer is not printed are laminated such that aportion is formed which defines and functions as the first mainsurface-side outer layer portion 12 in the vicinity of the first mainsurface TS1. On top of that, the dielectric sheet on which the patternof the first internal electrode layer 31 is printed and the dielectricsheet on which the pattern of the second internal electrode layer 32 isprinted are sequentially laminated alternately, such that a portion isformed which defines and functions as the inner layer portion 11. Onthis portion defining and functioning as the inner layer portion 11, apredetermined number of dielectric sheets in which the pattern of theinternal electrode layer is not printed are laminated, such that aportion is formed which defines and functions as the second mainsurface-side outer layer portion 13 in the vicinity of the second mainsurface TS2. Thus, a laminated sheet is produced.

The laminated sheet is pressed in the lamination direction byhydrostatic pressing, for example, such that a laminated block isproduced. Here, when performing the pressing, it is possible to formrecesses in the laminated block by crimping a transfer plate providedwith an uneven pattern on the surface, to a portion where recesses ofthe laminated block are to be formed. Here, by controlling the shape,size, depth, density, and the like of the concavo-convex patternprovided on the transfer plate, it is possible to form the desiredrecesses described in the present preferred embodiment.

The laminated block is cut to a predetermined size, such that laminatechips are cut out. At this time, corners and ridges of the laminatechips may be rounded by barrel polishing or the like.

By firing the laminate chips, the multilayer body 10 in which therecesses described in the present preferred embodiment are provided ismanufactured. The firing temperature depends on the materials of thedielectric layers 20 and the internal electrode layers 30. However, itis preferably about 900° C. or more and about 1400° C. or less, forexample.

When forming the base electrode layer with a thin film layer, a thinfilm layer defining and functioning as the base electrode layer isformed at a portion where the external electrode of the multilayer body10 is to be formed, by performing masking or other processing. The thinfilm layer is formed by a thin film forming method such as a sputteringmethod or a deposition method, for example. In the present preferredembodiment, the thin film layer is formed on the surface of themultilayer body 10 in which the plurality of recesses described in thepresent preferred embodiment are provided.

Thereafter, a plated layer is formed on the surface of the baseelectrode layer and the multilayer body made of a thin film layer. Inthe present preferred embodiment, as the plated layer, a plated layerincluding three layers, including a Cu plated layer, a Ni plated layer,and a Sn plated layer is formed.

In addition, when forming the base electrode layer with a fired layer, aconductive paste defining and functioning as a base electrode layer isapplied to the first side surface and the second side surface of themultilayer body 10. A conductive paste including a glass component andmetal is applied to the multilayer body 10 by, for example, a methodsuch as dipping. Thereafter, a firing process is performed to form thebase electrode layer. The temperature of the firing process at this timeis preferably about 700° C. or higher and about 900° C. or lower, forexample.

In a case in which the laminate chip before firing and the conductivepaste applied to the laminate chip are fired simultaneously, it ispreferable that the fired layer is formed by firing a layer to which aceramic material is added, instead of a glass component. At this time,it is particularly preferable to use, as the ceramic material to beadded, the same type of ceramic material as the dielectric layer 20. Inthis case, a conductive paste is applied to the laminate chip beforefiring, and the laminate chip and the conductive paste applied to thelaminate chip are fired simultaneously, such that the multilayer body 10having a fired layer formed therein is formed.

By such a manufacturing process, the multilayer ceramic capacitor 1 ismanufactured.

Hereinafter, a first modified example of the multilayer ceramiccapacitor 1 according to the present preferred embodiment will bedescribed. In the following description, the same or correspondingcomponents as those of the above-described preferred embodiment aredenoted by the same reference numerals, and detailed description thereofis omitted. FIG. 11A is a cross-sectional view showing a first modifiedexample of the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, and corresponding to FIG. 4 .

In the present modified example, the configuration of the externalelectrode 40 is different from that of the above-described preferredembodiment.

The first external electrode 40A includes a first base electrode layer50A and a first plated layer 60A. The first base electrode layer 50A ofthe present modified example includes a first thin film layer 51A and afirst fired layer 52A. The first plated layer 60A of the presentmodified example includes a first Ni plated layer 62A and a first Snplated layer 63A.

The second external electrode 40B includes a second base electrode layer50B and a second plated layer 60B. The second base electrode layer 50Bof the present modified example includes a second thin film layer 51Band a second fired layer 52B. The second plated layer 60B of the presentmodified example includes a second Ni plated layer 62B and a second Snplated layer 63B.

The first fired layer 52A is provided on the first side surface LS1.More specifically, the first fired layer 52A extends not only to thefirst side surface LS1 but also to a portion of the first main surfaceTS1.

The second fired layer 52B is provided on the second side surface LS2.More specifically, the second fired layer 52B extends not only to thesecond side surface LS2, but also to a portion of the first main surfaceTS1.

The first thin film layer 51A is provided on a portion of the first mainsurface TS1. The first thin film layer 51A overlaps on the first firedlayer 52A provided on a portion of the first main surface TS1, and theremaining portion is provided directly on the first main surface TS1 ofthe multilayer body 10.

The second thin film layer 51B is provided on a portion of the firstmain surface TS1. The second thin film layer 51B overlaps on the secondfired layer 52B provided on a portion of the first main surface TS1, andthe remaining portion is provided directly on the first main surface TS1of the multilayer body 10.

The thickness in the length direction L connecting the first sidesurface LS1 and the second side surface LS2 of the first fired layer 52Aprovided on the first side surface LS1 is preferably about 1 μm or moreand about 5 μm or less, for example. The thickness in the lengthdirection L connecting the first side surface LS1 and the second sidesurface LS2 of the second fired layer 52B provided on the second sidesurface LS2 is preferably about 1 μm or more and about 5 μm or less, forexample.

The first fired layer 52A and the second fired layer 52B may be made byapplying, for example, conductive pastes including glasses and metals toa multilayer body and firing. In addition, in a case in which thelaminate chip before firing and the conductive paste applied to thelaminate chip are fired simultaneously, it is preferable that the firedlayer is formed by firing a layer to which a ceramic material is addedinstead of a glass component. At this time, it is particularlypreferable to use, as the ceramic material to be added, the same type ofceramic material as the dielectric layer 20.

In addition, the first thin film layer 51A and the second thin filmlayer 51B may include, for example, sputtering electrodes as in theabove-described preferred embodiment.

The first plated layer 60A and the second plated layer 60B are notlimited to the two-layer structure, and may include, for example, athree-layer structure including Cu-plating, or may include another layerstructure as in the above preferred embodiment.

Also in the present modified example, the first main surface TS1 of themultilayer body 10 includes a plurality of first regions A1 covered withthe first external electrode 40A and the second external electrode 40Bdefining and functioning as a plurality of external electrodes 40. Inthe first region A1 on the first main surface TS1 of the multilayer body10, a plurality of recesses 80 each having a spherical curved surfacewith a mean inlet size of about 0.3 μm or more and about 10.5 μm or lessare provided, which are shown in the above-described preferredembodiment. Therefore, it is possible to ensure the anchor effectbetween the external electrode 40 and the multilayer body 10, and toincrease the adhesion strength between the external electrode 40 and themultilayer body 10. As a result, it is possible to reduce or prevent adecrease in the moisture resistance of the multilayer ceramic capacitor1. Also in the present modified example, it is preferable that the arearatio R occupied by the openings of the plurality of recesses 80 in thefirst region A1 is about 52% or more, for example. It is preferable thatother aspects such as the depth of the recess 80 are the same orsubstantially the same as those in the above-described preferredembodiment.

Hereinafter, a second modified example of the multilayer ceramiccapacitor 1 according to the present preferred embodiment will bedescribed. In the following description, the same or correspondingcomponents as those of the above-described preferred embodiment aredenoted by the same reference numerals, and a detailed descriptionthereof is omitted. FIG. 11B is a cross-sectional view showing a secondmodified example of the multilayer ceramic capacitor 1 according to thepresent preferred embodiment, and corresponding to FIG. 4 .

In the present modified example, the configuration of the externalelectrode 40 is different from that of the above-described preferredembodiment.

The first external electrode 40A includes a first base electrode layer50A and a first plated layer 60A. The first base electrode layer 50A ofthe present modified example includes a first fired layer 52A. The firstplated layer 60A of the present modified example includes a first Niplated layer 62A and a first Sn plated layer 63A.

The second external electrode 40B includes a second base electrode layer50B and a second plated layer 60B. The second base electrode layer 50Bof the present modified example includes a second fired layer 52B. Thesecond plated layer 60B of the present modified example includes asecond Ni plated layer 62B and a second Sn plated layer 63B.

The first base electrode layer 50A is provided on the first side surfaceLS1. The first base electrode layer 50A is connected to the firstinternal electrode layers 31. In the present preferred embodiment, thefirst base electrode layer 50A extends from the first side surface LS1to a portion of the first main surface TS1 of the first base electrodelayer.

The second base electrode layer 50B is provided on the second sidesurface LS2. The second base electrode layer 50B is connected to thesecond internal electrode layers 32. In the present preferredembodiment, the second base electrode layer 50B extends from the secondside surface LS2 to a portion of the first main surface TS1.

The first fired layer 52A included in the first base electrode layer 50Aand the second fired layer 52B included in the second base electrodelayer 50B may be obtained by, for example, firing conductive pastesincluding glasses and metals applied to a multilayer body. In addition,in a case in which the laminate chip before firing and the conductivepaste applied to the laminate chip are fired simultaneously, it ispreferable that the fired layer is formed by firing a layer to which aceramic material is added, instead of a glass component. At this time,it is particularly preferable to use, as the ceramic material to beadded, the same type of ceramic material as the dielectric layer 20.

The thickness in the length direction of the first base electrode layer50A provided on the first side surface LS1 is preferably, for example,about 15 μm or more and 160 μm or less in the middle portion in thelamination direction T and the width direction W of the first baseelectrode layer 50A.

The thickness in the length direction of the second base electrode layer50B provided on the second side surface LS2 is preferably, for example,about 15 μm or more and 160 μm or less in the middle portion in thelamination direction T and the width direction W of the second baseelectrode layer 50B.

The thickness in the lamination direction of the first base electrodelayer 50A provided on a portion of the first main surface TS1 ispreferably, for example, about 5 μm or more and about 40 μm or less inthe middle portion in the length direction L and the width direction Wof the first base electrode layer 50A provided on this portion.

The thickness of the second base electrode layer 50B provided on aportion of the first main surface TS1 in the lamination direction ispreferably, for example, about 5 μm or more and about 40 μm or less inthe middle portion in the length direction L and the width direction Wof the second base electrode layer 50B provided on this portion.

The first base electrode layer 50A may also be provided in a portion ofthe second main surface TS2. In this case, the thickness in thelamination direction of the first base electrode layer 50A provided inthis portion is, for example, preferably about 5 μm or more and about 40μm or less at the middle portion in the length direction L and the widthdirection W of the first base electrode layer 50A provided in thisportion.

The second base electrode layer 50B may also be provided in a portion ofthe second main surface TS2. In this case, the thickness in thelamination direction of the second base electrode layer 50B provided inthis portion is, for example, preferably about 5 μm or more and about 40μm or less at the middle portion in the length direction L and the widthdirection W of the second base electrode layer 50B provided in thisportion.

The first base electrode layer 50A may be provided on a portion of atleast one surface of the third side surface WS1 and the fourth sidesurface WS2. In this case, the thickness of the first base electrodelayer 50A provided in this portion in the width direction is preferably,for example, about 5 μm or more and about 40 μm or less at the middleportion in the length direction L and the lamination direction T of thefirst base electrode layer 50A provided in this portion.

The second base electrode layer 50B may be provided on a portion of atleast one surface of the third side surface WS1 and the fourth sidesurface WS2. In this case, the thickness of the second base electrodelayer 50B provided in this portion in the width direction is preferably,for example, about 5 μm or more and about 40 μm or less at the middleportion in the length direction L and the lamination direction T of thesecond base electrode layer 50B provided in this portion.

The first plated layer 60A and the second plated layer 60B are notlimited to the two-layer structure, and may have a three-layer structureincluding, for example, Cu-plating, or may include another layerstructure as in the above-described preferred embodiment.

Also in the present modified example, the first main surface TS1 of themultilayer body 10 includes a plurality of first regions A1 covered withthe first external electrode 40A and the second external electrode 40Bdefining and functioning as a plurality of external electrodes 40.Furthermore, in the first region A1 on the first main surface TS1 of themultilayer body 10, the plurality of recesses 80 each having a sphericalcurved surface having a mean inlet size of, for example, about 0.3 μm ormore and about 10.5 μm or less, which are shown in the above-describedpreferred embodiment, are provided. Therefore, it is possible to ensurethe anchor effect between the external electrode 40 and the multilayerbody 10, and to increase the adhesion strength between the externalelectrode 40 and the multilayer body 10. As a result, it is possible toreduce or prevent a decrease in the moisture resistance of themultilayer ceramic capacitor 1. Also in the present modified example, itis preferable that the area ratio R occupied by the openings of theplurality of recesses 80 in the first region A1 is about 52% or more,for example. It is preferable that other aspects such as the depth ofthe recess 80 are the same or substantially the same as those in theabove-described preferred embodiment.

Hereinafter, a third modified example of the multilayer ceramiccapacitor 1 according to the present preferred embodiment will bedescribed. In the following description, the same or correspondingcomponents as those of the above-described preferred embodiment aredenoted by the same reference numerals, and a detailed descriptionthereof is omitted. FIG. 12 is a cross-sectional view showing a thirdmodified example of the multilayer ceramic capacitor 1 of the presentpreferred embodiment, and corresponding to FIG. 4 .

In the present modified example, the connection structure of theinternal electrode layer 30 and the external electrode 40 is differentfrom the above-described preferred embodiment.

The first internal electrode layer 31 includes a first opposing portion31A facing the second internal electrode layer 32, and a first lead-outportion 31B extending from the first opposing portion 31A to the firstside surface LS1. However, in the present modified example, the firstlead-out portion 31B does not extend to the first side surface LS1.

The second internal electrode layer 32 includes a second opposingportion 32A facing the first internal electrode layer 31, and a secondlead-out portion 32B extending from the second opposing portion 32A tothe second side surface LS2. However, in the present modified example,the second lead-out portion 32B does not extend to the second sidesurface LS2.

The first external electrode 40A is provided only on the first mainsurface TS1 or the second main surface TS2 defining and functioning as amounting surface. Alternatively, the first external electrode 40A may beprovided on the first main surface TS1 and the second main surface TS2.In the present modified example, the first external electrode 40A isprovided only on a portion of the first main surface TS1 defining andfunctioning as a mounting surface. The first external electrode 40Aincludes a first base electrode layer 50A and a first plated layer 60Aprovided on the first base electrode layer 50A.

The second external electrode 40B is provided only on the first mainsurface TS1 or the second main surface TS2 defining and functioning as amounting surface. Alternatively, the second external electrode 40B maybe provided on the first main surface TS1 and the second main surfaceTS2. In the present modified example, the second external electrode 40Bis provided only on a portion of the first main surface TS1 defining andfunctioning as a mounting surface. The second external electrode 40Bincludes a second base electrode layer 50B and a second plated layer 60Bprovided on the second base electrode layer 50B.

The multilayer ceramic capacitor 1 of the present modified exampleincludes a first via connection portion 70A and a second via connectionportion 70B.

The first external electrode 40A and the first lead-out portion 31B ofthe first internal electrode layer 31 are electrically connected to eachother by the first via connection portion 70A.

The second external electrode 40B and the second lead-out portion 32B ofthe second internal electrode layer 32 are electrically connected toeach other by the second via connection portion 70B.

The first via connection portion 70A passes through a hole portion 20Hprovided in the dielectric layer 20 and a hole portion 31H provided inthe first internal electrode layer 31 of the multilayer body 10, andelectrically connects the first internal electrode layer 31 with thefirst external electrode 40A.

The second via connection portion 70B passes through the hole portion20H provided in the dielectric layer 20 and the hole portion 32Hprovided in the second internal electrode layer 32 of the multilayerbody 10, and electrically connects the second internal electrode layer32 with the second external electrode 40B.

When the first external electrode 40A is also provided on the secondmain surface TS2, the first via connection portion 70A may extend towardthe second main surface TS2 so as to electrically connect the firstinternal electrode layer 31 with the first external electrode 40Aprovided on the second main surface TS2.

When the second external electrode 40B is also provided on the secondmain surface TS2, the second via connection portion 70B may extendtoward the second main surface TS2 so as to electrically connect thesecond internal electrode layers 32 with the second external electrode40B provided on the second main surface TS2.

The shapes of the first via connection portion 70A and the second viaconnection portion 70B are not limited to a cylindrical or substantiallycylindrical shape and various shapes, such as a prismatic shape, may beused.

Also in the present modified example, the first main surface TS1 of themultilayer body 10 includes a plurality of first regions A1 covered withthe first external electrode 40A and the second external electrode 40Bdefining and functioning as a plurality of external electrodes 40. Inthe first region A1 on the first main surface TS1 of the multilayer body10, the plurality of recesses 80, each having a spherical curved surfacehaving a mean inlet size of about 0.3 μm or more and about 10.5 μm orless, for example, which are shown in the above-described preferredembodiment, are provided. Therefore, it is possible to ensure the anchoreffect between the external electrode 40 and the multilayer body 10, andto increase the adhesion strength between the external electrode 40 andthe multilayer body 10. As a result, it is possible to reduce or preventa decrease in the moisture resistance of the multilayer ceramiccapacitor 1. Also in the present modified example, the area ratio Roccupied by the openings 81 of the plurality of recesses 80 in the firstregion A1 is preferably about 52% or more, for example. Also in thepresent modified example, it is preferable that the area ratio Roccupied by the openings of the plurality of recesses 80 in the firstregion A1 is about 52% or more, for example. It is preferable that otheraspects such as the depth of the recess 80 are the same or substantiallythe same as those in the above preferred embodiment.

Hereinafter, a fourth modified example of the multilayer ceramiccapacitor 1 according to the present preferred embodiment will bedescribed. In the following description, the same or correspondingcomponents as those of the above-described preferred embodiment aredenoted by the same reference numerals, and a detailed descriptionthereof is omitted. FIG. 13A is a diagram showing a fourth modifiedexample of the multilayer ceramic capacitor 1 of the present preferredembodiment, and corresponding to FIG. 2 . FIG. 13B is an arrow view whenviewing the second main surface TS2 of the multilayer ceramic capacitor1 shown in FIG. 13A along the direction of the arrow XIIIB.

In the present modified example, the first external electrode 40A isprovided not only on a portion of the first side surface LS1 and thefirst main surface TS1, but also on a portion of the second main surfaceTS2.

In the present modified example, the second external electrode 40B isprovided not only on a portion of the second side surface LS2 and thefirst main surface TS1, but also on a portion of the second main surfaceTS2.

In the present modified example, as shown in FIG. 13B, the second mainsurface TS2 of the multilayer body 10 includes a plurality of thirdregions A3 covered by the first external electrode 40A and the secondexternal electrode 40B defining and functioning as the plurality ofexternal electrodes 40. The second main surface TS2 of the multilayerbody 10 includes a fourth region A4 exposed from the first externalelectrode 40A and the second external electrode 40B defining andfunctioning as the plurality of external electrodes 40.

In the present modified example, the plurality of third regions A3 aredivided into a region TS2A covered by the first external electrode 40A,and a region TS2B covered by the second external electrode 40B. That is,the plurality of third regions A3 are separated into the two regions inthe length direction L of the region TS2A located in the vicinity of thefirst side surface LS1 and a region TS2B located in the vicinity of thesecond side surface LS2. Furthermore, the fourth region A4 is providedbetween the plurality of third regions A3 so as to separate theplurality of third regions A3.

Also in the present modified example, the first main surface TS1 of themultilayer body 10 includes a plurality of first regions A1 covered withthe first external electrode 40A and the second external electrode 40Bdefining and functioning as the plurality of external electrodes 40. Inthe first region A1 on the first main surface TS1 of the multilayer body10, the plurality of recesses 80, each having a spherical curved surfacehaving a mean inlet size of about 0.3 μm or more and about 10.5 μm orless, which are shown in the above-described preferred embodiment, areprovided. Therefore, it is possible to ensure the anchor effect betweenthe external electrode 40 and the multilayer body 10, and to increasethe adhesion strength between the external electrode 40 and themultilayer body 10. As a result, it is possible to reduce or prevent adecrease in the moisture resistance of the multilayer ceramic capacitor1. Also in the present modified example, it is preferable that the arearatio R occupied by the openings of the plurality of recesses 80 in thefirst region A1 be 52% or more. It is preferable that other aspects suchas the depth of the recess 80 are the same as those in the abovepreferred embodiment.

Furthermore, in the present modified example, the plurality of recesses80 each having a spherical curved surface having a mean inlet size ofabout 0.3 μm or more and about 10.5 μm or less, similar to the recessesprovided in the first region A1, are also provided in the third regionA3 on the second main surface TS2 of the multilayer body 10. Therefore,even in this portion, it is possible to ensure the anchor effect betweenthe external electrode 40 and the multilayer body 10, and to increasethe adhesion strength between the external electrode 40 and themultilayer body 10. As a result, it is possible to reduce or prevent adecrease in the moisture resistance of the multilayer ceramic capacitor1. In the present modified example, it is preferable that the area ratioR occupied by the openings of the plurality of recesses 80 in the thirdregion A3 be also about 52% or more. It is preferable that other aspectssuch as the depth of the recess 80 are the same as those of the recessesprovided in the first region A1.

According to the configuration of the present modified example, mountingcan be performed not only on the first main surface TS1, but also on thesecond main surface TS2. As a result, the direction selection of themultilayer ceramic capacitor 1 at the time of packaging becomesunnecessary. Furthermore, when mounting the multilayer ceramic capacitor1, it is possible to draw up the solder to the main surface opposite tothe mounting surface. Therefore, the self-alignment property and theadhesion at the time of reflow mounting can be improved.

Hereinafter, a fifth modified example of the multilayer ceramiccapacitor 1 of the present preferred embodiment will be described. Inthe following description, the same components as those of the abovepreferred embodiment are denoted by the same reference numerals, and adetailed description thereof is omitted. FIG. 14A is a diagram showing afifth modified example of the multilayer ceramic capacitor 1 of thepresent preferred embodiment, and corresponding to FIG. 2 . FIG. 14B isan arrow view when viewing the first main surface TS1 of the multilayerceramic capacitor 1 shown in FIG. 14A along the direction of the arrowXIVB. FIG. 14C is an arrow view when viewing the third side surface WS1of the multilayer ceramic capacitor 1 shown in FIG. 14B along thedirection of the arrow XIVC.

In the present modified example, the first external electrode 40Aextends from the first side surface LS1 to a portion of the first mainsurface TS1 and a portion of the second main surface TS2, and further toa portion of the third side surface WS1 and a portion of the fourth sidesurface WS2. In other words, the first external electrode 40A isprovided on five surfaces including the first side surface LS1, thefirst main surface TS1, the second main surface TS2, the third sidesurface WS1, and the fourth side surface WS2.

In the present modified example, the second external electrode 40Bextends from the second side surface LS2 to a portion of the first mainsurface TS1 and a portion of the second main surface TS2, and further toa portion of the third side surface WS1 and a portion of the fourth sidesurface WS2. In other words, the second external electrodes 40B areprovided on five surfaces including the second side surface LS2, thefirst main surface TS1, the second main surface TS2, the third sidesurface WS1, and the fourth side surface WS2.

In the present modified example, as shown in FIG. 14C, the third sidesurface WS1 of the multilayer body 10 includes a plurality of fifthregions A5 covered by the first external electrode 40A and the secondexternal electrode 40B defining and functioning as a plurality ofexternal electrodes 40. The third side surface WS1 of the multilayerbody 10 includes a sixth region A6 exposed from the first externalelectrode 40A and the second external electrode 40B defining andfunctioning as the plurality of external electrodes 40.

In the present modified example, the plurality of fifth regions A5 aredivided into a region WS1A covered by the first external electrode 40A,and a region WS1B covered by the second external electrode 40B. That is,the plurality of fifth regions A5 are separated into two regions in thelength direction L, which are the region WS1A located in the vicinity ofthe first side surface LS1 and the region WS1B located in the vicinityof the second side surface LS2. The sixth region A6 is provided betweenthe plurality of fifth regions A5 so as to separate the plurality offifth regions A5.

Furthermore, in the present modified example, as shown in FIG. 14A, thefourth side surface WS2 of the multilayer body 10 includes a pluralityof seventh regions A7 covered with the first external electrode 40A andthe second external electrode 40B defining and functioning as theplurality of external electrodes 40. Furthermore, the fourth sidesurface WS2 of the multilayer body 10 includes an eighth region A8exposed from the first external electrode 40A and the second externalelectrode 40B defining and functioning as the plurality of externalelectrodes 40.

In the present modified example, the plurality of seventh regions A7 aredivided into a region WS2A covered by the first external electrode 40A,and a region WS2B covered by the second external electrode 40B. That is,the plurality of seventh regions A7 are separated into two regions inthe length L direction, which are the region WS2A located in thevicinity of the first side surface LS1 and the region WS2B located inthe vicinity of the second side surface LS2. Furthermore, the eighthregion A8 is provided between the plurality of seventh regions A7 so asto separate the plurality of seventh regions A7.

In the present modified example, as in the fourth modified example, theplurality of recesses 80 each having a spherical curved surface having amean inlet size of about 0.3 μm or more and about 10.5 μm or less, forexample, are provided in the first region A1 on the first main surfaceTS1 of the multilayer body 10 and in the third region A3 on the secondmain surface TS2 of the multilayer body 10. Therefore, the sameadvantageous effects as in the fourth modified example can be obtained.

Furthermore, in the present modified example, the plurality of recesses80 each having a spherical curved surface having a mean inlet size ofabout 0.3 μm or more and about 10.5 μm or less, for example, similar tothe recesses provided in the first region A1, are provided in the fifthregion A5 on the third side surface WS1 of the multilayer body 10 andthe seventh region A7 on the fourth side surface WS2 of the multilayerbody 10. Therefore, even in this portion, it is possible to ensure theanchor effect between the external electrode 40 and the multilayer body10, and to increase the adhesion strength between the external electrode40 and the multilayer body 10. As a result, it is possible to reduce orprevent a decrease in the moisture resistance of the multilayer ceramiccapacitor 1. In the present modified example, it is preferable that thearea ratio R occupied by the openings of the plurality of recesses 80 inthe fifth region A5 and the seventh region A7 is also about 52% or more,for example. It is preferable that other aspects such as the depth ofthe recess 80 are the same or substantially the same as those of therecess provided in the first region A1.

In addition, the formation of the plurality of recesses 80 in the fifthregion A5 and the seventh region A7 can be performed by, after thelaminate chip is cut out, crimping a transfer plate having aconcavo-convex pattern on its surface to a portion of the laminate chipwhere the recesses are to be formed.

With the configuration of the present modified example, when mountingthe multilayer ceramic capacitor 1, it is possible to draw up the solderto the third side surface WS1 and the fourth side surface WS2.Therefore, it is possible to further improve the self-alignment propertyand the adhesion at the time of reflow mounting.

Hereinafter, a sixth modified example of the multilayer ceramiccapacitor 1 according to the present preferred embodiment will beexplained. In the following description, the same components as those ofthe above-described preferred embodiment are denoted by the samereference numerals, and a detailed description thereof is omitted. FIG.15 is a diagram showing a sixth modified example of the multilayerceramic capacitor 1 of the present preferred embodiment, andcorresponding to FIG. 2 .

In the present modified example, the first external electrodes 40A areprovided not only on a portion of the first side surface LS1 and thefirst main surface TS1, but also on a portion of the third side surfaceWS1 and the fourth side surface WS2. In other words, the first externalelectrodes 40A are provided on the four surfaces of the first sidesurface LS1, the first main surface TS1, the third side surface WS1, andthe fourth side surface WS2.

In the present modified example, the second external electrode 40B isprovided, not only on a portion on the second side surface LS2 and thefirst main surface TS1, but also on a portion of the third side surfaceWS1 and the fourth side surface WS2. In other words, the second externalelectrodes 40B are provided on the four surfaces of the second sidesurface LS2, the first main surface TS1, the third side surface WS1, andthe fourth side surface WS2.

Also in the present modified example, the first main surface TS1 of themultilayer body 10 includes a plurality of first regions A1 covered withthe first external electrode 40A and the second external electrode 40Bas a plurality of external electrodes 40. In the first region A1 on thefirst main surface TS1 of the multilayer body 10, a plurality ofrecesses 80 having a spherical curved surface having a mean inlet sizeof about 0.3 μm or more and about 10.5 μm or less, for example, whichare shown in the above-described preferred embodiment, are provided.Therefore, to ensure the anchor effect between the external electrode 40and the multilayer body 10, it is possible to increase the adhesionstrength between the external electrode 40 and the multilayer body 10.As a result, it is possible to reduce or prevent a decrease in themoisture resistance of the multilayer ceramic capacitor 1. Also in thepresent modified example, it is preferable that the area ratio Roccupied by the openings of the plurality of recesses 80 in the firstregion A1 is about 52% or more, for example. It is preferable that otheraspects such as the depth of the recess 80 are the same or substantiallythe same as those in the above preferred embodiment.

Also in the present modified example, as in the fifth modified example,a plurality of recesses 80 having spherical curved surfaces having amean inlet size of about 0.3 μm or more and about 10.5 μm or less, forexample, are provided in the fifth region A5 on the third side surfaceWS1 of the multilayer body 10 and in the seventh region A7 on the fourthside surface WS2 of the multilayer body 10, similarly to the recessesprovided in the first region A1. Therefore, even in this portion, toensure the anchor effect between the external electrode 40 and themultilayer body 10, it is possible to increase the adhesion strengthbetween the external electrode 40 and the multilayer body 10. As aresult, it is possible to reduce or prevent a decrease in the moistureresistance of the multilayer ceramic capacitor 1.

Even in the configuration of the present modified example, when mountingthe multilayer ceramic capacitor 1, it is possible to draw up the solderto the third side surface WS1 and the fourth side surface WS2.Therefore, the self-alignment property and the adhesion at the time ofreflow mounting can be further improved. Furthermore, in the presentmodified example, the external electrode 40 is not provided on thesecond main surface TS2. Therefore, it is possible to reduce the heightof the multilayer ceramic capacitor 1 and to increase the volume of theeffective portion of the internal electrode layer 30 of the multilayerceramic capacitor 1 by the thickness of the external electrode 40 whichis omitted, such that it is possible to improve the degrees of freedomin design of the multilayer ceramic capacitor 1.

According to the multilayer ceramic capacitor 1 of the present preferredembodiment, the following advantageous effects are achieved.

(1) The multilayer ceramic capacitor 1 of the present preferredembodiment includes the multilayer body 10 including the plurality oflaminated dielectric layers 20 and the plurality of laminated internalelectrode layers 30, the multilayer body 10 further including the firstmain surface TS1 and the second main surface TS2 which oppose each otherin the lamination direction, the first side surface LS1 and the secondside surface LS2 which oppose each other in the length directionperpendicular or substantially perpendicular to the laminationdirection, and the third side surface WS1 and the fourth side surfaceWS2 which oppose each other in the width direction perpendicular orsubstantially perpendicular to the lamination direction and the lengthdirection, and the plurality of external electrodes 40 provided on aportion of the side surface including the four side surfaces LS1, LS2,WS1, and WS2, and on a portion of the first main surface TS1, the firstmain surface TS1 further including the plurality of first regions A1covered with the plurality of external electrodes 40 and the secondregion A2 exposed from the plurality of external electrodes 40, theplurality of first regions A1 of the first main surface TS1, eachincluding the plurality of recesses 80 provided therein, the pluralityof recesses 80 provided in each of the plurality of first regions A1,each including a spherical curved wall surface, and the plurality ofrecesses 80 provided in each of the plurality of first regions A1, eachhaving the average inlet size of about 0.3 μm or more and about 10.5 μmor less. With such a configuration, it is possible to ensure the anchoreffect between the external electrode 40 and the multilayer body 10,such that it is possible to increase the adhesion strength between theexternal electrode 40 and the multilayer body 10. As a result, it ispossible to reduce or prevent a decrease in the moisture resistance ofthe multilayer ceramic capacitor 1.

(2) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in each of the plurality of first regions A1, thearea ratio occupied by the openings of the plurality of recesses 80 isabout 52% or more. With such a configuration, the anchor effect betweenthe external electrode 40 and the multilayer body 10 is increased, suchthat it is possible to further increase the adhesion strength betweenthe external electrode 40 and the multilayer body 10.

(3) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, each of the plurality of external electrodes 40 isprovided on a portion of the second main surface TS2, the second mainsurface TS2 further includes the plurality of third regions A3 coveredby the plurality of external electrodes 40 and the fourth region A4exposed from the plurality of external electrodes 40, the plurality ofthird regions A3 of the second main surface TS2 each include theplurality of recesses 80 provided therein, the plurality of recesses 80provided in each of the plurality of third regions A3 each include aspherical curved wall surface, and the plurality of recesses provided ineach of the plurality of third regions A3 each have the average inletsize of about 0.3 μm or more and about 10.5 μm or less. With such aconfiguration, even in the third region A3, it is possible to ensure theanchor effect between the external electrode 40 and the multilayer body10, such that it is possible to increase the adhesion strength betweenthe external electrode 40 and the multilayer body 10. As a result, it ispossible to reduce or prevent a decrease in the moisture resistance ofthe multilayer ceramic capacitor 1.

(4) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in each of the plurality of third regions A3, thearea ratio occupied by the openings of the plurality of recesses 80 isabout 52% or more. With such a configuration, the anchor effect betweenthe external electrode 40 and the multilayer body 10 is increased, suchthat it is possible to further increase the adhesion strength betweenthe external electrode 40 and the multilayer body 10.

(5) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, each of the plurality of external electrodes 40 isprovided on a portion of the third side surface WS1, the third sidesurface WS1 further includes the plurality of fifth regions A5 coveredby the plurality of external electrodes 40 and the sixth region A6exposed from the plurality of external electrodes 40, the plurality offifth regions A5 of the third side surface WS1 each include theplurality of recesses 80 provided therein, the plurality of recesses 80provided in each of the plurality of fifth regions A5 each include aspherical curved wall surface, and the plurality of recesses 80 providedin each of the plurality of fifth regions A5 each have the average inletsize of about 0.3 μm or more and about 10.5 μm or less. With such aconfiguration, even in the fifth region A5, it is possible to ensure theanchor effect between the external electrode 40 and the multilayer body10, such that it is possible to increase the adhesion strength betweenthe external electrode 40 and the multilayer body 10. As a result, it ispossible to reduce or prevent a decrease in the moisture resistance ofthe multilayer ceramic capacitor 1.

(6) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in each of the plurality of fifth regions A5, thearea ratio occupied by the openings of the plurality of recesses 80 isabout 52% or more. With such a configuration, the anchor effect betweenthe external electrode 40 and the multilayer body 10 is increased, suchthat it is possible to further increase the adhesion strength betweenthe external electrode 40 and the multilayer body 10.

(7) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, each of the plurality of external electrodes 40 isprovided on a portion of the fourth side surface WS2, the fourth sidesurface WS2 further includes the plurality of seventh regions A7 coveredby the plurality of external electrodes 40 and the eighth region A8exposed from the plurality of external electrodes 40, the plurality ofseventh regions A7 of the fourth side surface WS2 each include theplurality of recesses 80 provided therein, the plurality of recesses 80provided in each of the plurality of seventh regions A7 each include aspherical curved wall surface, and the plurality of recesses provided ineach of the plurality of seventh regions A7 each have the average inletsize of about 0.3 μm or more and about 10.5 μm or less. With such aconfiguration, even in the seventh region A7, it is possible to ensurethe anchor effect between the external electrode 40 and the multilayerbody 10, such that it is possible to increase the adhesion strengthbetween the external electrode 40 and the multilayer body 10. As aresult, it is possible to reduce or prevent a decrease in the moistureresistance of the multilayer ceramic capacitor 1.

(8) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in each of the plurality of seventh regions A7,the area ratio occupied by the openings of the plurality of recesses 80is about 52% or more. With such a configuration, the anchor effectbetween the external electrode 40 and the multilayer body 10 isincreased, such that it is possible to further increase the adhesionstrength between the external electrode 40 and the multilayer body 10.

(9) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the plurality of external electrodes 40 includesthe first external electrode 40A and the second external electrode 40B,the first external electrode 40A is provided at least on a portion ofthe first side surface LS1 and a portion of the first main surface TS1,the second external electrode 40B is provided at least on a portion ofthe second side surface LS2 and a portion of the first main surface TS1,and the plurality of first regions A1 includes the first region TS1Acovered with the first external electrode 40A in the vicinity of thefirst side surface LS1, and the first region TS1B covered with thesecond external electrode 40B in the vicinity of the second side surfaceLS2. Even in a multilayer ceramic capacitor including two such externalelectrodes 40, it is possible to achieve the advantageous effects of thepresent disclosure.

(10) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the ceramic particles included in the dielectriclayers 20 have the average particle size of about 0.1 μm or more andabout 1 μm or less. With such a configuration, it is possible to reducethe thickness of the dielectric layer 20 of the multilayer ceramiccapacitor 1, such that it is possible to obtain the large multilayerceramic capacitor 1 having a large capacitance density per volume.

(11) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in the plurality of first regions A1, theplurality of recesses 80 have the average inlet size of about twice ormore and about 20 times or less the average particle size of the ceramicparticles included in the dielectric layers 20. With such aconfiguration, it is possible to appropriately provide the recesses 80,and furthermore, it is possible to reduce or prevent the stressconcentration on the multilayer body 10, while ensuring the anchoreffect between the external electrode 40 and the multilayer body 10.Therefore, it is possible to achieve both the adhesion strength betweenthe external electrode 40 and the multilayer body 10 and the strength ofthe multilayer body 10.

(12) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the plurality of internal electrode layers 30include the plurality of first internal electrode layers 31 and theplurality of second internal electrode layers 32, the multilayer body 10includes the plurality of dielectric layers 20 sandwiched between thefirst internal electrode layer 31 and the second internal electrodelayer 32, and in the plurality of first regions A1, the plurality ofrecesses 80 have the average inlet size of about 0.2 times or more andabout 5 times or less the thickness of the dielectric layers 20. Withsuch a configuration, it is possible to use appropriate ceramicparticles, each having a smaller average particle size, and thus it ispossible to appropriately provide the recesses 80 while increasing thecapacitance density by reducing the thickness of the dielectric layer 20sandwiched between the first internal electrode layer 31 and the secondinternal electrode layer 32. Therefore, it is possible to ensure thecapacitance density per volume of the multilayer ceramic capacitor 1,and ensure the adhesion strength between the external electrode 40 andthe multilayer body 10.

(13) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in the first regions A1, the plurality of recesses80 have the average depth of about 0.1 μm or more and about 5 μm orless. With such a configuration, it is possible to reduce or prevent thestress concentration on the multilayer body 10 while ensuring the anchoreffect between the external electrode 40 and the multilayer body 10,such that it is possible to achieve both the strength of the multilayerbody 10 and the adhesion strength and the multilayer body 10 between theexternal electrode 40.

(14) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the plurality of external electrodes 40 eachinclude at least the base electrode layer 50 provided in close contactwith the plurality of first regions A1 of the first main surface TS1,and an outer electrode layer covering the base electrode layer 50, andthe plurality of recesses 80 provided in each of the plurality of firstregions A1 have the average depth which is larger than the thickness ofthe base electrode layer 50, and smaller than the thickness of the outerelectrode layer. With such a configuration, it is possible to increasethe anchor effect between the plated layer 60 included in the outerelectrode layer and the plurality of recesses 80 of the multilayer body10 in which the base electrode layer 50 is coated, while increasing theadhesion force by increasing the surface of the multilayer body 10 andthe contact area of the thin film layer 51 included in the baseelectrode layer 50, such that it is possible to increase the adhesionstrength between the external electrode 40 and the multilayer body 10 asa whole.

(15) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the plurality of recesses 80 provided in each ofthe first regions A1 include recesses having an inlet size larger thanthe average inlet size and recesses having an inlet size smaller thanthe average inlet size, and the average depth of the recesses having aninlet size smaller than the average inlet size is smaller than theaverage depth of the recesses having an inlet size larger than theaverage inlet size. Thus, it is possible to appropriately adjust theanchor effect between the external electrode 40 and the multilayer body10.

Second Preferred Embodiment

Hereinafter, a multilayer ceramic capacitor 1 according to a secondpreferred embodiment of the present invention will be described. In thefollowing, the same or corresponding components as those of the firstpreferred embodiment are denoted by the same reference numerals, and thedetailed descriptions thereof are omitted. FIG. 16A is a diagram showinga state in which the multilayer ceramic capacitor 1 of the presentpreferred embodiment is embedded in a component built-in board 300. FIG.16B is an enlarged view of an XVIB portion in FIG. 16A, and is anenlarged cross-sectional view schematically showing a microscopiccross-sectional shape in the vicinity of the surface layer portion ofthe second region A2 of the multilayer body 10.

The multilayer ceramic capacitor 1 of the present preferred embodimentincludes a plurality of recesses 80 not only on the surface of themultilayer body 10 on which the first external electrode 40A and thesecond external electrode 40B defining and functioning as a plurality ofexternal electrodes are provided, but also on the surface of themultilayer body 10 on which the first external electrode 40A and thesecond external electrode 40B defining and functioning as a plurality ofexternal electrodes are not provided.

As shown in FIG. 16A, the component built-in board 300 includes themultilayer ceramic capacitor 1, and a board 301 including the multilayerceramic capacitor 1 therein. The board 301 includes a core material 310mainly made of resin, and a via hole conductor 320.

The material included in the core material 310 is, for example, glassepoxy resin. However, the material included in the core material 310 isnot limited to a glass epoxy resin. For example, it may be a polyimideresin or the like.

The via hole conductor 320 electrically connects the external electrode40 of the multilayer ceramic capacitor 1, with a wiring pattern (notshown) printed on the board 301. The metal included in the via holeconductor 320 is, for example, Cu. However, the metal included in thevia hole conductor 320 is not limited to Cu, and may be, for example,Au, Pt, or the like.

The external electrode 40 of the multilayer ceramic capacitor 1 may bethe same or substantially the same as that of the first preferredembodiment. However, the external electrode 40 preferably includes anoutermost layer formed by Cu plating.

The first external electrode 40A includes a first base electrode layer50A and a first plated layer 60A. For example, the first base electrodelayer 50A may include a first thin film layer 51A, and the first platedlayer 60A may include a first Cu plated layer 61A.

The second external electrode 40B includes a second base electrode layer50B and a second plated layer 60B. For example, the second baseelectrode layer 50B may include a second thin film layer 51B, and thesecond plated layer 60B may include a second Cu plated layer 61B.

Thus, for example, in a case of forming the via hole conductor 320 withCu, the external electrode 40 and the via hole conductor 320 include thesame or substantially the same type of metal. Therefore, the connectionresistance of both of the connection portions is reduced, and it ispossible to reduce or prevent deterioration of the boardcharacteristics.

Similar to the first preferred embodiment, the first main surface TS1 ofthe multilayer body 10 includes a second region A2 exposed from thefirst external electrodes 40A and the second external electrodes 40Bdefining and functioning as the plurality of external electrodes 40.

In the present preferred embodiment, as shown in FIG. 16B, a pluralityof recesses 80 each having a spherical curved surface having a meaninlet size of about 0.3 μm or more and about 10.5 μm or less, forexample, similar to the recesses provided in the first region A1, arealso provided in the second region A2 on the first main surface TS1 ofthe multilayer body 10. Therefore, in this portion, it is possible toensure the anchor effect between the core material 310 included in theboard 301 and the multilayer body 10, and increase the adhesion strengthbetween the core material and the multilayer body 10. In addition, inthe present modified example, it is preferable that the area ratio Roccupied by the openings of the plurality of recesses 80 in the secondregion A2 is also about 52% or more, for example. It is preferable thatother aspects such as the depth of the recess 80 are the same orsubstantially the same as those of the recess provided in the firstregion A1.

As described above, it is preferable that the plurality of recesses 80are also provided on the surface of the multilayer body 10 on which thefirst external electrode 40A and the second external electrode 40Bdefining and functioning as the plurality of external electrodes are notprovided. With such a configuration, even when used in applications suchas embedding the multilayer ceramic capacitor 1 in the componentbuilt-in board or a high-density package, it is still possible to ensurethe adhesion strength between the external electrode 40 and themultilayer body 10. In addition, even between the surface of themultilayer body 10 and a sealing agent, such as a resin, used for acomponent built-in board or a high-density package, the adhesionstrength can be improved by the anchor effect. Therefore, it is possibleto further improve the moisture resistance of the multilayer ceramiccapacitor 1.

In addition, the plurality of recesses 80 each having a spherical curvedsurface having a mean inlet size of about 0.3 μm or more and about 10.5μm or less, for example, similar to the recesses provided in the firstregion A1, may also be provided on the second main surface TS2 of themultilayer body 10. In addition, the plurality of recesses 80 eachhaving a spherical curved surface having a mean inlet size of about 0.3μm or more and about 10.5 μm or less, for example, similar to therecesses provided in the first region A1, may be provided on the thirdside surface WS1 and the fourth side surface WS2 of the multilayer body10. As a result, the adhesion strength can be improved by the anchoreffect between the surface of the multilayer body 10 and the sealingagent such as a resin used for the component built-in board or thehigh-density package.

In addition, in the multilayer ceramic capacitor 1 of the mode shown inFIGS. 13A and 13B and FIGS. 14A to 14C as the modified examples of thefirst preferred embodiment, the plurality of recesses 80 each having aspherical curved surface having a mean inlet size of about 0.3 μm ormore and about 10.5 μm or less, for example, similar to the recessesprovided in the first region A1, may be provided in the fourth region A4on the second main surface TS2. Furthermore, in the multilayer ceramiccapacitor 1 of the mode shown in FIGS. 14A to 14C and FIG. 15 as themodified examples of the first preferred embodiment, the plurality ofrecesses 80 each having a spherical curved surface having a mean inletsize of about 0.3 μm or more and about 10.5 μm or less, for example,similar to the recesses provided in the first region A1, may be providedin the sixth region A6 of the third side surface WS1 and the eighthregion A8 of the fourth side surface WS2. As a result, the adhesionstrength can be improved by the anchor effect between the surface of themultilayer body 10 and the sealing agent such as a resin used for thecomponent built-in board or the high-density package.

According to the multilayer ceramic capacitor 1 of the present preferredembodiment, the following advantageous effects are obtained in additionto the above-described (1) to (15).

(16) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the second region A2 in addition to the pluralityof first regions A1 includes the plurality of recesses 80 providedtherein, the plurality of recesses 80 provided in the second region A2each include a spherical curved wall surface, and the plurality ofrecesses 80 provided in the second region A2 each have the average inletsize of about 0.3 μm or more and about 10.5 μm or less. With such aconfiguration, even when used in applications such as embedding themultilayer ceramic capacitor 1 in the component built-in board or ahigh-density package, it is possible to ensure the adhesion strengthbetween the external electrode 40 and the multilayer body 10. Inaddition, even between the surface of the multilayer body 10 and asealing agent such as a resin used for a component built-in board or ahigh-density package, the adhesion strength can be improved by theanchor effect.

(17) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in the second region A2, the area ratio occupiedby the openings of the plurality of recesses 80 is about 52% or more. Asa result, the anchor effect is improved even between the surface of themultilayer body 10 and the sealing agent such as a resin used for thecomponent built-in board or the high-density package, such that theadhesion strength can be improved.

(18) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, the fourth region A4 in addition to the pluralityof third regions A3 includes the plurality of recesses 80 providedtherein, the plurality of recesses 80 provided in the fourth region A4each include a spherical curved wall surface, and the plurality ofrecesses 80 provided in the fourth region A4 each have the average inletsize of about 0.3 μm or more and about 10.5 μm or less. With such aconfiguration, even when used in applications such as embedding themultilayer ceramic capacitor 1 in the component built-in board or ahigh-density package, it is possible to ensure the adhesion strengthbetween the external electrode 40 and the multilayer body 10. Inaddition, even between the surface of the multilayer body 10 and asealing agent such as a resin used for a component built-in board or ahigh-density package, the adhesion strength can be improved by theanchor effect.

(19) In the multilayer ceramic capacitor 1 according to the presentpreferred embodiment, in the fourth region A4, the area ratio occupiedby openings of the plurality of recesses 80 is about 52% or more. Withsuch a configuration, the anchor effect is improved even between thesurface of the multilayer body 10 and the sealing agent such as a resinused for the component built-in board or the high-density package, suchthat the adhesion strength can be improved.

Third Preferred Embodiment

Hereinafter, a multilayer ceramic capacitor 1 according to a thirdpreferred embodiment of the present invention will be described. In thefollowing description, a detailed description for the same orsubstantially the same configuration as that of the first preferredembodiment is omitted. FIG. 17 is an external perspective view of amultilayer ceramic capacitor 101 according to the present preferredembodiment. FIG. 18 is an exploded perspective view of the multilayerbody 110 included in the multilayer ceramic capacitor 101 of the presentpreferred embodiment. FIG. 19 is an external perspective view of themultilayer body 110 included in the multilayer ceramic capacitor 101 ofthe present preferred embodiment. FIG. 20A is an arrow view when viewinga first main surface TS1 of the multilayer ceramic capacitor 101 shownin FIG. 17 in the direction along the arrow XXA. FIG. 20B is an arrowview when viewing the first main surface TS1 of the multilayer body 110shown in FIG. 19 along the direction of the arrow XXB. FIGS. 20A and 20Billustrate that a third side surface WS1 is provided on the lower sidethereof.

The multilayer ceramic capacitor 101 of the present preferred embodimentis different from the first preferred embodiment in aspects such as theshapes of a multilayer body 110 and external electrodes 140.

The multilayer ceramic capacitor 101 includes the multilayer body 110and external electrodes 140.

As shown in FIGS. 17 to 20B, the multilayer body 110 includes a firstmain surface TS1 and a second main surface TS2 which oppose each otherin the lamination direction T, a first side surface LS1 and a secondside surface LS2 which oppose each other in the length direction Lperpendicular or substantially perpendicular to the lamination directionT, and a third side surface WS1 and a fourth side surface WS2 whichoppose each other in the width direction W perpendicular orsubstantially perpendicular to the lamination direction T and the lengthdirection L.

The dimensions of the multilayer body 110 are not particularly limited.However, when the dimension in the length direction L of the multilayerbody 10 is defined as an L dimension, the dimension in the widthdirection W of the multilayer body 10 is defined as a W dimension, andthe dimension in the lamination direction T of the multilayer body 10 isdefined as a T dimension, it is preferable, for example, that the Ldimension is about 0.43 mm or more and about 0.73 mm or less, about0.85≤ (W dimension)/(L dimension)≤ about 1.0, and the T dimension beabout 50 μm or more and about 90 μm or less.

When the dimension in the length direction L of the multilayer ceramiccapacitor 101 including the external electrode 140 is defined as an LCdimension, the dimension in the width direction W of the multilayerceramic capacitor 101 including the external electrode 140 is defined asa WC dimension, and the dimension in the lamination direction T of themultilayer ceramic capacitor 101 including the external electrode 140 isdefined as a TC dimension, it is preferable that the LC dimension isabout 0.45 mm or more and about 0.75 mm or less, about 0.85≤ (WCdimension)/(LC dimension)≤about 1.0, and the T dimension is preferablyabout 70 μm or more about 110 μm or less, for example.

As shown in FIG. 18 , the multilayer body 110 includes an inner layerportion 11, and a first main surface-side outer layer portion 12 and asecond main surface-side outer layer portion 13 provided so as tosandwich the inner layer portion 11 in the lamination direction T.

The inner layer portion 11 includes a plurality of dielectric layers 120and a plurality of internal electrode layers 130. In the laminationdirection T, the inner layer portion 11 includes internal electrodelayers 130 from the internal electrode layer 130 located closest to thefirst main surface TS1 to the internal electrode layer 130 locatedclosest to the second main surface TS2. In the inner layer portion 11, aplurality of internal electrode layers 130 oppose each other with thedielectric layer 120 interposed therebetween.

The plurality of internal electrode layers 130 include a plurality offirst internal electrode layers 131 and a plurality of second internalelectrode layers 132. The plurality of first internal electrode layers131 are each provided on the dielectric layer 120. The plurality ofsecond internal electrode layers 132 are each provided on the dielectriclayer 120. The plurality of first internal electrode layers 131 and theplurality of second internal electrode layers 132 are alternatelyprovided via a dielectric layer 120 in the lamination direction T of themultilayer body 10. The first internal electrode layers 131 and thesecond internal electrode layers 132 each sandwich the dielectric layers120.

The first internal electrode layer 131 includes a first opposing portion131A facing the second internal electrode layer 132, a first lead-outportion 131B extending from the first opposing portion 131A to the firstside surface LS1 and the third side surface WS1, and a second lead-outportion 131C extending from the first opposing portion 131A to thesecond side surface LS2 and the fourth side surface WS2. The firstlead-out portion 131B is exposed at the first side surface LS1 and thethird side surface WS1. The second lead-out portion 131C is exposed atthe second side surface LS2 and the fourth side surface WS2.

The second internal electrode layer 132 includes a second opposingportion 132A facing the first internal electrode layer 131, a thirdlead-out portion 132B extending from the second opposing portion 132A tothe second side surface LS2 and the third side surface WS1, and a fourthlead-out portion 132C extending from the second opposing portion 132A tothe first side surface LS1 and the fourth side surface WS2. The thirdlead-out portion 132B is exposed at the second side surface LS2 and thethird side surface WS1. The fourth lead-out portion 132C is exposed atthe first side surface LS1 and the fourth side surface WS2.

In the present preferred embodiment, the first opposing portion 131A andthe second opposing portion 132A oppose each other with the dielectriclayers 120 interposed therebetween, such that a capacitance isgenerated, and the characteristics of a capacitor are provided.

The shape of the first opposing portion 131A is not particularlylimited, but is preferably rectangular or substantially rectangular.However, the corners of the rectangular or substantially rectangularshape may be rounded, or the corners of the rectangular or substantiallyrectangular shape may be slanted. The shapes of the first lead-outportion 131B and the second lead-out portion 131B are not particularlylimited, but are preferably rectangular or substantially rectangularsuch that a portion thereof overlaps with the first opposing portion131A. However, the corners of the rectangular or substantiallyrectangular shape may be rounded, or the corners of the rectangular orsubstantially rectangular shape may be slanted.

The shape of the second opposing portion 132A is not particularlylimited, but is preferably rectangular or substantially rectangular.However, the corners of the rectangular or substantially rectangularshape may be rounded, or the corners of the rectangular or substantiallyrectangular shape may be slanted. The shapes of the third lead-outportion 132B and the fourth lead-out portion 132B are not particularlylimited, but are preferably a rectangular or substantially rectangularshape in which a portion thereof overlaps with the second opposingportion 132A. However, the corners of the rectangular or substantiallyrectangular shape may be rounded, or the corners of the rectangular orsubstantially rectangular shape may be slanted.

The first main surface-side outer layer portion 12 is located in thevicinity of the first main surface TS1 of the multilayer body 110. Thefirst main surface-side outer layer portion 12 includes a plurality ofdielectric layers 120 located between the first main surface TS1 and theinternal electrode layer 130 closest to the first main surface TS1.

The second main surface-side outer layer portion 13 is located in thevicinity of the second main surface TS2 of the multilayer body 110. Thesecond main surface-side outer layer portion 13 includes a plurality ofdielectric layers 120 located between the second main surface TS2 andthe internal electrode layer 130 closest to the second main surface TS2.

The materials of the dielectric layer 120 and the internal electrodelayer 130 may be the same or substantially the same as those of thefirst preferred embodiment. As in the first preferred embodiment, theparticle size of the ceramic particles used in the dielectric layer ispreferably about 0.1 μm or more and about 1 μm or less, for example.Thus, it is possible to reduce the thickness of the dielectric layer,such that it is possible to obtain a multilayer ceramic capacitor havinga large capacitance density per volume.

The external electrode 140 includes a first external electrode 140A, asecond external electrode 140B, a third external electrode 140C, and afourth external electrode 140D. The four external electrodes 140A, 140B,140C, and 140D are provided in a state of being separated into fourcorners or substantially four corners when viewing the first mainsurface TS1 or the second main surface TS2 along the laminationdirection T.

The first external electrode 140A is provided on the multilayer body110. The first external electrode 140A preferably extends from the firstside surface LS1 and the third side surface WS1 to a portion of thefirst main surface TS1 and a portion of the second main surface TS2.That is, it is preferable that the first external electrodes 140A isprovided in a portion of the first side surface LS1 in the vicinity ofthe third side surface WS1, a portion of the third side surface WS1 inthe vicinity of the first side surface LS1, a portion of the first mainsurface TS1, and a portion of the second main surface TS2. The firstexternal electrode 140A may be provided on one of a portion of the firstmain surface TS1 or a portion of the second main surface TS2, whichdefines and functions as a mounting surface, instead of both of the mainsurfaces. In other words, the cross-sectional shape of the firstexternal electrode 140A may be in an L-shape.

The second external electrode 140B is provided on the multilayer body110. The second external electrode 140B preferably extends from thefirst side surface LS1 and the fourth side surface WS2 to a portion ofthe first main surface TS1 and a portion of the second main surface TS2.That is, it is preferable that the second external electrode 140B isprovided on a portion of the first side surface LS1 in the vicinity ofthe fourth side surface WS2, a portion of the fourth side surface WS2 inthe vicinity of the first side surface LS1, a portion of the first mainsurface TS1, and a portion of the second main surface TS2. The secondexternal electrode 140B may be provided not on both main surfaces, butrather on one of a portion of the first main surface TS1 or a portion ofthe second main surface TS2 defining and functioning as a mountingsurface. In other words, the cross-sectional shape of the secondexternal electrode 140B may be in an L-shape.

The third external electrode 140C is provided on the multilayer body110. The third external electrode 140C preferably extends from thesecond side surface LS2 and the third side surface WS1 to a portion ofthe first main surface TS1 and a portion of the second main surface TS2.That is, it is preferable that the third external electrode 140C isprovided on a portion of the second side surface LS2 in the vicinity ofthe third side surface WS1, a portion of the third side surface WS1 inthe vicinity of the second side surface LS2 side, a portion of the firstmain surface TS1, and a portion of the second main surface TS2. Thethird external electrodes 140C may be provided on one of a portion ofthe first main surface TS1 or a portion of the second main surface TS2,which defines and functions as a mounting surface, instead of both mainsurfaces. In other words, the cross-sectional shape of the thirdexternal electrode 140C may be in an L-shape.

The fourth external electrode 140D is provided on the multilayer body110. The fourth external electrode 140D preferably extends from thesecond side surface LS2 and the fourth side surface WS2 to a portion ofthe first main surface TS1 and a portion of the second main surface TS2.That is, it is preferable that the second external electrode 140B beprovided in a portion of the second side surface LS2 in the vicinity ofthe fourth side surface WS2 side, a portion of the fourth side surfaceWS2 in the vicinity of the second side surface LS2 side, a portion ofthe first main surface TS1, and a portion of the second main surfaceTS2. The fourth external electrode 140D may be provided on one of aportion of the first main surface TS1 or a portion of the second mainsurface TS2, which defines and functions as a mounting surface, insteadof both main surfaces. In other words, the cross-sectional shape of thefourth external electrode 140D may be in an L-shape.

As shown in FIG. 20B, the first main surface TS1 of the multilayer body110 includes a plurality of first regions A1 covered with the firstexternal electrode 140A, the second external electrode 140B, the thirdexternal electrode 140C, and the fourth external electrode 140D,defining and functioning as the plurality of external electrodes 140.Furthermore, the first main surface TS1 of the multilayer body 110includes a second region A2 exposed from the first external electrode140A, the second external electrode 140B, the third external electrode140C, and the fourth external electrode 140D, defining and functioningas the plurality of external electrodes 140.

In the present preferred embodiment, the plurality of first regions A1include four separated regions that are covered with the first externalelectrode 140A, the second external electrode 140B, the third externalelectrode 140C, and the fourth external electrode 140D, respectively.Furthermore, the second region A2 is provided between the plurality offirst regions A1 so as to separate the plurality of first regions A1.

Furthermore, in the present preferred embodiment as well, in theplurality of first regions A1 on the first main surface TS1 of themultilayer body 110, the plurality of recesses 80 each having aspherical curved surface having a mean inlet size of about 0.3 μm ormore and about 10.5 μm or less, for example, which are shown in thefirst preferred embodiment, are provided. Therefore, it is possible toensure the anchor effect between the external electrode 140 and themultilayer body 110, and to increase the adhesion strength between theexternal electrode 140 and the multilayer body 110. As a result, it ispossible to reduce or prevent a decrease in the moisture resistance ofthe multilayer ceramic capacitor 101. Also in the present preferredembodiment, it is preferable that, in the first region A1, the arearatio R occupied by the openings of the plurality of recesses 80 isabout 52% or more, for example. It is preferable that other aspects suchas the depth of the recess 80 are the same or substantially the same asthose of the first preferred embodiment.

Furthermore, as in the second preferred embodiment, the plurality ofrecesses 80 each having a spherical curved surface having a mean inletsize of about 0.3 μm or more and about 10.5 μm or less, similar to therecesses provided in the first region A1, may be provided in the secondregion A2 on the first main surface TS1 of the multilayer body 110.Thus, it is possible to obtain the same or substantially the sameadvantageous effects as in the second preferred embodiment.

Also in the present preferred embodiment, as shown in FIG. 19 , thesecond main surface TS2 of the multilayer body 110 includes a pluralityof third regions A3 covered with a plurality of external electrodes 140.Furthermore, the second main surface TS2 of the multilayer body 110includes a fourth area A4 exposed from the plurality of externalelectrodes 140. Here, as described in the modified examples of the firstpreferred embodiment, the third region A3 may also be provided with theplurality of recesses 80 each having a spherical curved surface havingan average inlet size of about 0.3 μm or more and about 10.5 μm or less,for example, similar to the recesses provided in the first region A1.Furthermore, in the fourth region A4, as described in the secondpreferred embodiment, the plurality of recesses 80 each having aspherically curved surface having an average inlet size of about 0.3 μmor more and about 10.5 μm or less, for example, similar to the recessesprovided in the first region A1, may be provided.

Hereinafter, a first modified example of the multilayer ceramiccapacitor 101 of the present preferred embodiment will be described. Inthe following description, the same or corresponding components as thoseof the above preferred embodiment are denoted by the same referencenumerals, and a detailed description thereof is omitted. FIG. 21 is anexternal perspective view showing a multilayer ceramic capacitor 101 ofthe first modified example of the present preferred embodiment, andcorresponding to FIG. 17 .

In the present modified example, the shapes of external electrodes 140are different from the above-described preferred embodiment.

In the present modified example, the plurality of external electrodes140 are provided on portions of the first main surface TS1, but are notprovided on the second main surface TS2. That is, a plurality ofexternal electrodes of the present modified example each have anL-shaped cross-sectional shape.

The first external electrode 140A extends from the first side surfaceLS1 and the third side surface WS1 to a portion of the first mainsurface TS1.

The second external electrode 140B extends from the first side surfaceLS1 and the fourth side surface WS2 to a portion of the first mainsurface TS1.

The third external electrode 140C extends from the second side surfaceLS2 and the third side surface WS1 to a portion of the first mainsurface TS1.

The fourth external electrode 140D extends from the second side surfaceLS2 and the fourth side surface WS2 to a portion of the first mainsurface TS1.

Also in the present modified example, in the plurality of first regionsA1 on the first main surface TS1 of the multilayer body 110, theplurality of recesses 80 each having a spherical curved surface having amean inlet size of about 0.3 μm or more and about 10.5 μm or less, forexample, which are shown in the first preferred embodiment, areprovided. Therefore, it is possible to ensure the anchor effect betweenthe external electrode 140 and the multilayer body 110, and to increasethe adhesion strength between the external electrode 140 and themultilayer body 110. As a result, it is possible to reduce or prevent adecrease in the moisture resistance of the multilayer ceramic capacitor101. Also in the present preferred embodiment, it is preferable that, inthe first region A1, the area ratio R occupied by the openings of theplurality of recesses 80 is about 52% or more, for example. It ispreferable that other aspects such as the depth of the recess 80 are thesame or substantially the same as those of the first preferredembodiment.

Hereinafter, a second modified example of the multilayer ceramiccapacitor 101 according to the present preferred embodiment will bedescribed. In the following description, the same or correspondingcomponents as those of the above-described preferred embodiment aredenoted by the same reference numerals, and a detailed descriptionthereof is omitted. FIG. 22 is an external perspective view of amultilayer ceramic capacitor 101 of the second modified example of thepresent preferred embodiment, and corresponding to FIG. 17 . FIG. 23 isan exploded perspective view of a multilayer body 110 included in themultilayer ceramic capacitor 101 of the present modified example, and isa diagram corresponding to FIG. 18 .

In the present modified example, the shapes of the internal electrodelayer 130 and the external electrode 140 are different from those in theabove-described preferred embodiments.

The plurality of internal electrode layers 130 each include a pluralityof first internal electrode layers 131 and a plurality of secondinternal electrode layers 132.

The first internal electrode layer 131 extends to the first side surfaceLS1 of the multilayer body 110 with a first lead-out portion 131B, andextends to the second side surface LS2 of the multilayer body 110 with asecond lead-out portion 131C. More specifically, the first lead-outportion 131B extends to the first side surface LS1 in the vicinity ofthe third side surface WS1 of the multilayer body 110, and the secondlead-out portion 131C extends to the second side surface LS2 in thevicinity of the fourth side surface WS2 of the multilayer body 110. Thefirst internal electrode layer 131 is not exposed at the third sidesurface WS1 or the fourth side surface WS2 of the multilayer body 110.

The second internal electrode layer 132 extends to the first sidesurface LS1 of the multilayer body 110 with a third lead-out portion132B, and extends to the second side surface LS2 of the multilayer bodywith a fourth lead-out portion 132C. More specifically, the thirdlead-out portion 132B extends to the first side surface LS1 in thevicinity of the fourth side surface WS2 of the multilayer body 110, andthe fourth lead-out portion 132C extends to the second side surface LS2in the vicinity of the third side surface WS1 of the multilayer body110. The second internal electrode layer 132 is not exposed at the thirdside surface WS1 or the fourth side surface WS2 of the multilayer body110.

The first external electrode 140A includes a notch 140AS therein on thethird side surface WS1.

The second external electrode 140B includes a notch 140BS therein on thefourth side surface WS2.

The third external electrode 140C includes a notch 140CS therein on thethird side surface WS1.

The fourth external electrode 140D includes a notch 140DS therein on thefourth side surface WS2.

The first lead-out portions 131B of the first internal electrode layer131 may extend to one of the first side surface LS1, the second sidesurface LS2, the third side surface WS1, and the fourth side surfaceWS2. In this case, the second lead-out portion 131C of the firstinternal electrode layer 131 may extend to one side surface other thanthe side from which the first lead-out portion 131B extends.

Furthermore, the third lead-out portion 132B of the second internalelectrode layer 132 may extend to one of the first side surface LS1, thesecond side surface LS2, the third side surface WS1, and the fourth sidesurface WS2. In this case, the fourth lead-out portion 132C of thesecond internal electrode layer 132 may extend to one side surface otherthan the side from which the third lead-out portion 132B extends.

In addition, when viewing the multilayer ceramic capacitor 1 in thelamination direction T, it is preferable that a straight line connectingthe first lead-out portion 131B and the second lead-out portion 131C ofthe first internal electrode layer 131, and a straight line connectingthe third lead-out portion 132B and the fourth lead-out portion 132C ofthe second internal electrode layer 132 intersect.

Furthermore, in the four side surfaces LS1, LS2, LS3, and LS4 of themultilayer body 10, it is preferable that the first lead-out portion131B of the first internal electrode layer 131 and the fourth lead-outportion 132C of the second internal electrode layer 132 extend toopposite locations, and the second lead-out portion 131C of the firstinternal electrode layer 131 and the third lead-out portion 132B of thesecond internal electrode layer 132 extend to opposite locations.

Also in the present modified example, in the plurality of first regionsA1 on the first main surface TS1 of the multilayer body 110, theplurality of recesses 80 each having a spherical curved surface having amean inlet size of about 0.3 μm or more and about 10.5 μm or less, forexample, which are shown in the first preferred embodiment, areprovided. Therefore, it is possible to ensure the anchor effect betweenthe external electrode 140 and the multilayer body 110, and to increasethe adhesion strength between the external electrode 140 and themultilayer body 110. As a result, it is possible to reduce or prevent adecrease in the moisture resistance of the multilayer ceramic capacitor101. Also in the present preferred embodiment, in the first region A1,the area ratio R occupied by the openings of the plurality of recesses80 is preferably about 52% or more, for example. It is preferable thatother aspects such as the depth of the recess 80 are the same orsubstantially the same as those of the first preferred embodiment.

According to the multilayer ceramic capacitor 101 of the presentpreferred embodiment, the following advantageous effects are obtained inaddition to the abovementioned (1) to (19).

(20) In the multilayer ceramic capacitor 101 according to the presentpreferred embodiment, the plurality of external electrodes 140 includethe first external electrode 140A, the second external electrode 140B,the third external electrode 140C, and the fourth external electrode140D, the first external electrode 140A is provided at least on aportion of the first main surface TS1, a portion of the first sidesurface LS1, and a portion of the third side surface WS1, the secondexternal electrode 140B is provided at least on a portion of the firstmain surface TS1, a portion of the first side surface LS1, and a portionof the fourth side surface WS2, the third external electrode 140C isprovided at least on a portion of the first main surface TS1, a portionof the second side surface LS2, and a portion of the third side surfaceWS1, the fourth external electrode 140D is provided at least on aportion of the first main surface TS1, a portion of the second sidesurface LS2, and a portion of the fourth side surface WS2, and theplurality of first regions A1 includes a region covered with the firstexternal electrode 140A, a region covered with the second externalelectrode 140B, a region covered with the third external electrode 140C,and a region covered with the fourth external electrode 140D. Even in amultilayer ceramic capacitor including such four external electrodes 40,it is still possible to obtain the advantageous effects of variouspreferred embodiments of the present invention.

EXAMPLES

According to the above-described non-limiting example of a manufacturingmethod, multilayer ceramic capacitors were produced as samples of theExamples, and a moisture resistance reliability test and a foldingresistance test were performed.

1. Manufacture of Multilayer Ceramic Capacitors

As samples of the Examples, multilayer ceramic capacitors having thefollowing specifications were manufactured with the structure shown inFIGS. 1 to 7 in accordance with the manufacturing method of the firstpreferred embodiment.

-   -   Dimensions of multilayer ceramic capacitors: L×W×T=about 0.6        mm×about 0.3 mm×about 0.11 mm    -   Material of dielectric layer (main component): BaTiO₃    -   Plurality of recesses having spherical curved surfaces are        provided in first region A1 of multilayer body    -   Average inlet size of plurality of recesses: see Table 1    -   Area ratio occupied by openings of plurality of recesses in        first region A1: see Table 1    -   Material of internal electrode layer: Ni    -   Structure of external electrode    -   Base electrode layer: thin film layer mainly made of Ni/Cr alloy        is formed by sputtering    -   Plated layer: three-layer structure of Cu plated layer, Ni        plated layer, and Sn plated layer from the base body side

As a sample of the Comparative Examples, a multilayer ceramic capacitorincluding no plurality of recesses in the first region A1 of themultilayer body was manufactured. Except for a plurality of recesses notbeing provided, the sample was manufactured with the same orsubstantially the same specifications as the samples of the Examples.

2. Measurement and Testing

Next, the prepared samples were subjected to measurement and testingaccording to the following measurement method and test method.

(1) Moisture Resistance Reliability Test

Each sample was mounted on a glass epoxy board using eutectic solder.Thereafter, each sample was put into a high-temperature andhigh-humidity bath at about 125° C. and about 95% RH (relativehumidity), and subjected to a moisture resistance accelerated test underthe conditions of about 3.2 V for about 72 hours. The samples in whichthe insulation resistance value (IR value) was lowered by two digits ormore were determined to be samples in which the moisture resistance wasdeteriorated, and the number of the samples was counted.

(2) Transverse Test

Tests were performed according to three-point bending tests using astainless steel support and a stainless steel push bar. The distancebetween the support points was about 0.5 mm. A hemispherical push rodwith a tip of R=about 0.05 mm was used. The samples were provided on thesupport base central portion, and brought into contact with the push rodat the central portion of the upper surface of the samples (the secondmain surface of the multilayer ceramic capacitor). A downward externalforce was applied to the push rod to confirm whether or not the samplesfractured. The magnitude of the external force was about 2.0 N, thenumber of samples measured was 20, and the number of samples fracturedwas counted. The number of fractured chips is preferably 3 or less, andmore preferably 0.

3. Test Results

The test results are given in Table 1.

TABLE 1 SAMPLE NO. COMPARATIVE EXAMPLE 1 2 3 4 5 6 7 8 9 10 11 AREARATIO OF NO RECESSES 79 80 78 81 82 81 79 26 52 77 98 RECESSES (%) INLETSIZE OF NO RECESSES 0.2 0.3 1.1 3.2 6.9 10.5 12.2 1.0 1.1 1.1 0.9RECESSES (μm) MOISTURE RESISTANCE 5/10 3/10 0/10 0/10 0/10 0/10 0/100/10 2/10 0/10 0/10 0/10 RELIABILITY TEST- DETERIORATION TRANSVERSETEST- 0/10 0/10 0/10 0/10 0/10 1/10 2/10 5/10 0/10 0/10 0/10 0/10FRACTURE EVALUATION P P E E E G G P G E E E E: Excellent, G: Good, P:Poor(not applicable)

As shown in Table 1, favorable results were obtained from Samples 2 to 6and 8 to 11 of the Examples as compared to the sample of the ComparativeExamples. That is, when the inlet size of the recess was about 0.3 μm ormore and about 10.5 μm or less, favorable results were obtained in boththe moisture resistance reliability test and the transverse test. Inparticular, when the inlet size of the recess was about 0.3 μm or moreand about 3.2 μm or less, extremely favorable balanced results wereobtained in both the moisture resistance reliability test and thefolding test.

It was also discovered from the test results that it is preferable thatthe area ratio of the recesses, that is, the area ratio occupied by theopenings of the plurality of recesses in the first region A1, is about52% or more. When the area ratio of the recesses was about 26%, themoisture resistance reliability was inferior to that when the area ratioof the recesses is about 52% or more. However, even in the samples inwhich the area ratio of the recess was about 26%, the advantageouseffect of improving the moisture resistance reliability compared withthe Comparative Examples was obtained.

In view of the above results, it is possible for the ceramic capacitoraccording to preferred embodiments of the present invention to enablethe anchor effect to be generated between the external electrode and themultilayer body, and to increase the adhesion strength between theexternal electrode and the multilayer body. As a result, it is possibleto reduce or prevent the intrusion of moisture or the like from theinterface between the multilayer body and the external electrode, suchthat it is possible to reduce or prevent a decrease in moistureresistance of the multilayer ceramic capacitor.

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing from the scopeand spirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

What is claimed is:
 1. A multilayer ceramic capacitor comprising: amultilayer body including a plurality of laminated dielectric layers anda plurality or laminated internal electrode layers, the multilayer bodyfurther including a first main surface and a second main surface whichoppose each other in a lamination direction, a first side surface and asecond side surface which oppose each other in a length directionperpendicular or substantially perpendicular to the laminationdirection, and a third side surface and a fourth side surface whichoppose each other in a width direction perpendicular or substantiallyperpendicular to the lamination direction and the length direction; anda plurality of external electrodes including a first external electrode,a second external electrode, a third external electrode, and a fourthexternal electrode; wherein the fir external electrode is provided on atleast a portion of the first main surface, a portion of the first sidesurface, and a portion of the third side surface; the second externalelectrode is provided on at least a portion of the first main surface, aportion of the first side surface, and a portion of the fourth sidesurface; the third external electrode is provided on at least a portionof the first main surface, a portion of the second side surface, and aportion of the third side surface; the fourth external electrode isprovided on at least a portion of the first main surface, a portion ofthe second side surface, and a portion of the fourth side surface; andthe first main surface includes a plurality of first regions and asecond region; the plurality of first regions include a region coveredwith the first external electrode, a region covered with the secondexternal electrode, a region covered with the third external electrode,and a region covered with the fourth external electrode; and the secondregion includes a region exposed from the plurality of externalelectrodes; the plurality of first regions each include a plurality ofrecesses therein; the plurality of recesses in each of: the plurality offirst regions each include a spherical curved wall surface; and theplurality of recesses in each of the plurality of first regions eachhave an average inlet size of about 0.3 μm or more and about 10.5 μm orless.
 2. The multilayer ceramic capacitor according to claim wherein, ineach of the plurality of first regions, an area ratio occupied byopenings of the plurality of recesses is about 52% or more.
 3. Themultilayer ceramic capacitor according to claim 1, wherein each of theplurality of external electrodes is also provided on a portion of thesecond main surface; the second main surface includes a plurality ofthird regions covered by the plurality of external electrodes and afourth region exposed from the plurality of external electrode; theplurality of third regions of the second main surface each include aplurality of recesses therein; the plurality of recesses in each of theplurality of third regions each include a spherical curved wall surface;and the plurality of recesses in each of the plurality of third regionseach have an average inlet size of about 0.3 μm or more and about 10.5μm or less.
 4. The multilayer ceramic capacitor according to claim 3,wherein, in each of the plurality of third regions, an area ratiooccupied by openings of the plurality of recesses is about 52% or more.5. The multilayer ceramic capacitor according to claim 1, wherein thesecond region, in addition to the plurality of first regions, includes aplurality of recesses therein; the plurality of recesses in the secondregion each include a spherical curved wall surface; and the pluralityof recesses provided in the second region each have an average inletsize of about 0.3 μm or more and about 10.5 μm or less.
 6. Themultilayer ceramic capacitor according to claim 5, wherein, in thesecond region, an area ratio occupied by openings of the plurality ofrecesses is about 52% or more.
 7. The multilayer ceramic capacitoraccording to claim 3, wherein the fourth region, in addition to theplurality of third regions, includes a plurality of recesses providedtherein; the plurality of recesses in the fourth region each include aspherical curved wall surface; and the plurality of recesses provided inthe fourth region each have an average inlet size of about 0.3 μm ormore and about 10.5 μm or less.
 8. The multilayer ceramic capacitoraccording to claim 3, wherein, in the fourth region, an area ratiooccupied by openings of the plurality of recesses is about 52% or more.9. The multilayer ceramic capacitor according to claim 1, wherein, inthe plurality of first regions, the plurality of recesses have anaverage inlet size of about twice or more and about 20 times or less theaverage particle size of the ceramic particles included in the pluralityof dielectric layers.
 10. The multilayer ceramic capacitor according toclaim 1, wherein the plurality of internal electrode layers includeplurality of first internal electrode layers and a plurality of secondinternal electrode layers; the multilayer body includes the plurality ofdielectric layers sandwiched between the plurality of first internalelectrode layers and the plurality of second internal, electrode layers;and in the plurality of first regions, the plurality of recesses have anaverage inlet size of about 0.2 times or more and about 5 times or lessa thickness of the dielectric layers.
 11. The multilayer ceramiccapacitor according to claim 1, wherein, in the plurality of firstregions, the plurality of recesses have an average depth of about 0.1 μmor more and about 5 μm or less.
 12. The multilayer ceramic capacitoraccording to claim 1, wherein a dimension in the length direction of themultilayer body is about 0.43 mm or more and about 0.73 mm or less. 13.The multilayer ceramic capacitor according to claim 1, wherein adimension in the width direction of the multilayer body is about0.85≤(width dimension)/(length dimension)≤about 1.0.
 14. The multilayerceramic capacitor according to claim 1, wherein a dimension in thelamination direction of the multilayer body is about 50 μm or more andabout 90 μm or less.